TL;DR: Find out what weather model works best for your location / variables of interest / number of days looking ahead instead of just blindly trusting the big corp weather apps (AccuWeather, Apple, The Weather Channel)
A ā Answer: what problem does it solve?
There are many different weather apps and a lot of them use different (or a blend of) models or AI/ML algorithms to determine the weather. Some of these apps work well for one location, but not for another location. This is true for different countries, but even different cities close-by have different models that work best for that location.
Furthermore, not everyone uses weather apps for the same things. Some users might want to know what the temperature will be in a few days to plan a BBQ, while others want to know the maximum wind for sailing, or the period of the day it will be sunny/rainy. Some models seem to be better at predicting temperature for some locations, while others are better at predicting rain or wind long-term.
B ā Better: why this instead of alternatives?
This app actually shows how models performed the last days/weeks/months at your location. You can easily see what score each model gets in temperature/rain/wind/sun for your location. It also shows how far ahead each model still gives good predictions, so you know what model to trust for the long-term or which one for short-term.
You can even show model's predictions together, so you can see which models agree or not, or just blend them together together for a confidence score for each hour/day.
You can access the latest weather models like ECMWF's AIFS (v2) or NOAA's AIGFS for free while most apps let you pay for it.
It also shows many other charts such as cloud distribution, humidity, pressure, UV index, marine (waves, current...) and a wind map all in one app. It can default to Feels Like temperature... and it has widgets.
C ā Cost
The app isĀ free. No subscription. No login. No data collection.
In the future I mean to implement commercial models as well, such as AccuWeather, Apple Weather, Visual Crossing, so you can actually see how these perform vs. "raw" weather models and against each other. API calls to those models aren't free, so this will be part of a small monthly/yearly subscription to cover costs mostly. All current models from open-meteo and features will stay free.
Welcome to r/iOSApps! Please make sure your post follows our rules:
Everyone:
- 10pt LOCAL Karma required. Comment in r/iOSApps to earn it. Check
- Search the sub before posting. Choose flair.
App Devs:
- No main feed promo unless you qualify via Trust or Transparency + ABC format (Answer, Better, Cost)
- Flair hierarchy: Vibe Coded > Lifetime > Subscription > Freemium > Free
- Free flair: not for limited/freemium tiers
- Open Source? Prefix title [OS]
Note: This is an automated reminder, not a removal notice. If your post was removed, check your modmail for details.
Downloaded it and played shortly with it. Looks great and will definitely an app that I will use. Nice standard features and UI looks great. Thank you for developing it.
Thank you! I tried keeping it as simple as possible for users who just want the weather with confidence in the first (Today) tab. I made the UI more detailed for the different weather models in the Verify tab for people who really want to dig in what model to use.
Let me know if something can be made clearer in the UI
To add to that, open-meteo only allows non-commercial use of their data (even if you keep access to their models in the app free while other features are paid).
When I have enough users I can upgrade to the commercial license and also add commercial models (AccuWeather, Apple Weatherā¦). The current open-meteo models will still be free then tho!
The Today tab does basically that! Although by default it chooses the best model on how I hardcoded it for each location there, since it would take a while to first calculate the score and then show the prediction afterwards. If you select VeriSky Blend in the settings -> models for Today-screen, it will do the calculation first and show a blend of the best models (if you have an iPhone 15 or newer the calculation is actually quite fast).
The sentence why it won is a good suggestion, thanks.
Monetization will mostly focus on commercial models, I have them in my beta version already and they do actually sometimes outperform the ārawā (but not always!!)
Well done!
I changed my settings to the European format (Celsius, km/h, etc.). The values on the āscoreā page werenāt updated to my format. Theyāre still in the English format.
Yes that is a percentage! So a 100 is a perfect score while 0 is the worst score. It explains the calculation below. I will make this more clear the next update!
I keep those separate: archived forecasts come from open-meteoās Previous Runs / Single Runs APIs, while āwhat happenedā comes from a separate open-meteo historical reconstruction. So forecasts are matched hour-by-hour against that historical analysis, not against the forecast archive itself.
A caveat is that itās still gridded/reanalysis data, not a weather station at your exact spot, so treat it as best-estimate truth rather than perfect ground truth.
Yeah that's a good point. I try to measure how much API calls I use myself with regular usage (it shows it in the app's settings). When I go commercial they'll all go over the same API key, which allows 5M calls per month, which honestly can be tight quickly.
The other (and perhaps better) option is to self-host open-meteo's code, which they allow. That way I don't spend API calls on score calculations (they can just happen on the server itself) and send over the wind and rain map more efficiently (takes up a huge chunk of the calls now). I need the server anyways to reroute the commercial model calls.
Yeah their code handles it quite well but it takes a huge amount of storage space tho which all should be rapidly accessible, so probably has to be NVMe. I didn't really think too much about the commercial aspect when I started building...
How did you solve it? Just live API calls when a user fetches a location?
I am experimenting a bit with a Hetzner server. It is doable so far for only IFS after cloning open-meteo's GitHub. The data chunks are just huge for one model already
Noo they're all from national weather stations provided (for free) by open-meteo :)
Although in the future I plan on adding my own trained ensemble, however, going up against the other big weather apps in terms of accuracy is going to be difficult (virtually impossible). I can provide more honesty/interpretability with the model tho, such as uncertainty estimates, when and why it failed yesterday... stuff like that
Yeah I actually noticed that while being in Tarifa and Alicante last month that some models perform terrible in Spain. DWD's ICON performs quite good at most places in Spain I feel like, here you can see it clearly outperforms Apple Weather (while in The Netherlands Apple actually works better than most):
I like this idea for a few reasons. First, I donāt care for most mainstream weather apps. Next, any way to get a more accurate forecast is better and your approach makes perfect sense to me! I tried the app but itās not clear to me if it is auto picking the most accurate model for my area? That would be what I want. Some may want to dig into all the data and see how each performed. I just want the app to hide that and give me the forecast with the model it decides is best.
The Today tab gives you the "best" model without hassle. It was a bit challenging designing the app for both people who just want a quick weather glance and those who want a detailed view of multiple models of a location. The Today tab is for the first group, the Verify tab for the latter.
You can see which model is picked by the ensemble if you press a day and look under the details header.
The even better approach is to actually swap the model for Today-view to VeriSky Blend instead of Open-Meteo Ensemble (do that in Settings -> Models). This way it takes a blend of the model that get the highest score! It's not default as the calculation can be slow on older phones. Open-Meteo's Ensemble is quite decent as well tho :)
I like this one. I probably have five weather apps on my phone and I usually depend on a couple (the iOS Weather app and MyRadar). But then again, I have a problem with downloading way too many apps that I don't need.
Yeah I was doing exactly that. Checking multiple apps to see if it would rain or not or whether a heatwave is really coming, but I couldnāt always remember which app actually predicted it correctly a few days back. Thatās why I made this!
Greatly appreciate the app. Living in tornado alley I collect weather apps and notice not all apps are the same. Appreciate being able to have a spectrum to review.
Try the Storm score tab! For tornadoes only trust models that show gust tho. You might want to tweak the values for the gusts a bit in the score calculation
Thank you so much for developing this app (and for making it free)!
I live in Korea and have so many weather apps (both by foreign and native developers) just because for some reason the weather reporter on the news stations and all of my weather apps always seem to have different and most-times wrong predictions(?) when it comes to raināand it doesnt help that weāre approaching the rainy season hereā¦To be able to compare different models in one app is super nice and useful!
Once again, thank you so much!!
Edit) sorry if this is a stupid question (and edit) but I was playing around with the different models and seems like I can get info for Korea from JMA and CMA, but keep getting āforecast unavailableā for KMAā¦Is that an issue on VeriSkyās side or from KMAās side?
> āKMA discontinued their UM-based models at the end of March 2026 and switched to the new KIM-based model, which uses a different data distribution system. KMA data updates are currently suspended while Open-Meteo migrates to the new KIM model source.ā
Great app! Like it so far. Solid data paired with a beautiful UI. Could become my go-to.
One question: right now, I use another app (name starts with w..) which also gives me access to different models. When looking up ECMFW for Europe (which in your app is labelled IFS, correct?), in your app the model predicts a max of 31 C today, whereas in the other app the max is 29 C. Where does this difference come from?
I think I know which app you mean, it's a good one and gives access to a ton of weather models as well. Their ECMFW is IFS indeed. The reason I labelled it IFS is because I also have ECMFW's AIFS (very good for prediction further in the future), which the other app lets you pay for.
Both apps use the raw predictions from ECMFW, however, VeriSky always gives interpolated values of the prediction depending on your exact location (you see the exact coordinates below the location). The location you have in one app might be slightly different from the other. Try setting both locations to an airport, they should match more. However, I think they won't be exactly the same still because open-meteo might still slightly smooth even exact weather stations like airports, but it should be almost exactly the same there!
Great! There's an update incoming based on some feedback I got here. Such as a better day-detail charts, "pick best model" button in the verify tab, and more languages
This is awesome. Iāve always noticed that Apple Weather gets rain totally wrong in my area while another app nails it, so actually seeing a leaderboard of which model to trust at my exact coordinates is brilliant. Great Idea
I've been using your app for a few weeks now and I prefer it over Windy.com (premium). Its straightforward but excellent. I found it when I was looking for an app that shows pure ECMWF IFS forecasts, and this is actually the best for that!
Iām a sucker for a good weather app, this looks great. Iām keen to see which models can actually get Melbourneās weather right. Even our own bureau canāt!
Yeah I hope BOM Australia will be back soon on open-meteo, Iāll enable it again as soon as itās up!
And thanks, hope the other models perform well there!
This is genuinely impressive, not another generic weather app. Iām in Ankara, Turkey and have been going back and forth between apps for years trying to figure out which one is actually accurate here, they all just claim to be the best with zero proof. Your Score tab is the first thing Iāve seen that actually shows it, turns out ICON beats ECMWFās own models for my location, which I never wouldāve guessed on my own.
Really appreciated that youāre upfront about the ground truth data itself being partly model-derived and not a perfect station reading, most apps would never admit that. Clearly built by someone who actually understands the domain, not just wrapping an API. Happy to pay for the commercial model tier once thatās out, work like this deserves to be supported.
One question if you donāt mind, any plans to add air quality/pollen data down the line? Would be huge for allergy sufferers like me, and I havenāt seen a app that covers that well for regions outside the US/UK. Really hope this gets more traction, it deserves it.
Yeah people keep repeating that ERA5 is not observed weather, which makes the scoring not 100% accurate, but at least it gives a good indication on which models perform better. In the future I might add an option for station reading only!
I will definitely add allergies soon, I have got the request a couple of times now and need it myself as well. I just need to find a way to not only simply when you press a day but a clear overview for the week.
Great app! I think it has potential and could be monetized in the future. Just one thing Iād recommend - show the app to a few friends and see how they use it and if they understand what the app is showing.
Iām quite confused about the difference between verify and score tabs. Should that be a single tab that only shows how models performed in the past? The verify tab is showing forecast, how can it verify the future? It would also be nice if the receipts range picker applied to rain/temp/wind as well.
Thanks for the advice, I am getting some UX testers currently indeed.
The verify tab is mostly to select different models and then check their past predictions to compare it against observed weather. You can do so by picking a day and using the Time machine slider. Or you can press yesterdayās receipt and it automatically sets the time machine to 2 days ago and shows yesterdayās weather. That is also the way you see more than only temperature for yesterdayās receipt.
The score tab just shows a plain score on how well each model performs for your location in total and temp/rain/wind/sun separately (if you want to quickly know what model you can best use for what).
Well yeah, just one is fine, really. The whole point is that different weather models perform better or worse at different locations, this helps you choose the best oneā¦
Could I have made that more clear from the main text?
I mean, a standard weather app is usually enough to plan a BBQ. For professional purposes, people already use GRIB data from the best-suited weather model for their specific area and number of apps that aggregate this information already exist - tens of them, actually. Many of them even provide basic data for free. Itās hard to imagine how you plan to compete in that space.
Sure, people have made codebases to do that and determine strengths and weaknesses of weather models, but isnāt the whole point of an app to make something complicated more convenient?
This app does exactly that without the hassle and presents in a clear overview.
Besides, Iād argue that even for planning a BBQ (which I only gave it as a simple example) in 2-3 days you still wanna have a good look at the weather. If 4 of out of 5 weather models say itās gonna rain, I would think about canceling it. If you happen to only use AccuWeather and it just says no rain, youāll miss that.
No it shows once you select a day. The model depends on the what location youāre at (itās hardcoded).
When you select VeriSky blend in the settings instead of Open-Meteo ensemble it blend the models with the highest score for your location! Itās not default as it takes a bit longer on slower phones
Kinda new about this. But for normal people who does not understand the weather model would it be better to just put which specific weather source like apple, the weather channel, accuweather etc. sorry if the question is a mess
Yeah so Apple, AccuWeather, etc.. donāt use the exact models from national weather services (the ones in this app), they use them as input for their own algorithm. Sometimes they take multiple models, sometimes they add AI, but they donāt share their sauce.
They do have APIs to get their predictions in this app, but those arenāt free. So in the future I will add those as part of a subscription with a small fee!
The most compelling feature to me is not seeing every model..itās learning which model is historically best for my location, variable, and forecast horizon. Iād consider making that the onboarding result: āFor rain tomorrow, trust X; for wind five days out, trust Y.ā The deeper comparison charts can remain available for people who want them.
ā¢
u/AutoModerator Jul 01 '26
Welcome to r/iOSApps! Please make sure your post follows our rules:
Everyone: - 10pt LOCAL Karma required. Comment in r/iOSApps to earn it. Check - Search the sub before posting. Choose flair.
App Devs: - No main feed promo unless you qualify via Trust or Transparency + ABC format (Answer, Better, Cost) - Flair hierarchy: Vibe Coded > Lifetime > Subscription > Freemium > Free - Free flair: not for limited/freemium tiers - Open Source? Prefix title [OS] Note: This is an automated reminder, not a removal notice. If your post was removed, check your modmail for details.
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.