It says in the description that it's 'Windy Maps by Seznam.cz' (which appears to be some kind of news site?), but the developer is listed as 'Windyty SE', and the developer website is listed as https://www.windy.com/, which appears to be a weather map. Doesn't exactly inspire confidence.
Sorry, I guess I must have gotten redirected when logged in or something like that. It is indeed the app you are linking to and the developer of both mapy.cz and windy maps is indeed Seznam.cz, which is the "Czech Google" as much as Yandex is for Russians for example. They are the #1 Czech news/email/search/maps/... provider and have been since the nineties. Windy.com is an interactive weather map company, but also founded and owned by the same owner as Senznam.cz, and I guess they tried to combine the English rebrand of the maps with the ability to show interactive weather, which is indeed a bit odd.
I'm okay with it, because as an American I'm inherently distrustful of eastern European TLDs like cz ru etc but Windy is a truly amazing weather website so it inspires confidence (and having a mobile version has been needed for awhile imo)
It says in the description that it's 'Windy Maps by Seznam.cz' (which appears to be some kind of news site?), but the developer is listed as 'Windyty SE', and the developer website is listed as https://www.windy.com/, which appears to be a weather map. Doesn't exactly inspire confidence.