you could offer the game on itch because they allow to add a tip (and an optional minimum amount). Most platforms also dont stop you from oss+paid and even with being propritary+paid there is no guarantee people will buy it or when that you break even.
You could also try to sell the game for the first years and then open source it when its either clear that nobody pays or when it did make enough money.
just to give another reason: proving the software is safe.
Basically the entire reason why F-Droid apps are all safe is because the code is easily checkable.
But i still understand why someone wants to go proprietary. Just wanted to add that reason
wanted to check it out but after 60% being obvious ai i noped out without buying anything
if the child can read setting something like an ad campaing of can be pretty straigtforward.
A few years ago i found out that my reddit accound had some free credit and was thinking about using it for something silly and it was very very easy. (seems like companies like getting money for ads) The free credit was not much so they definetly wanted me to spend more
they look like they are perfect for stickers
500 cigarettes
becuse no one told about alternatives:
Waterfox/Librewolf + uBlock + my addons + whatever other addons i like
They are like Firefox but stripped off mozillas bs to something thats cleaner. And because they are based on Firefox (Gecke engine) they also support manifest v2 and all the really good adblockers (i mean uBlock)
i suggest waterfox or librewolf instead of normal firefox because they are just better. Waterfox also has the bonus of having an android app and allowing to download all addons (but some will not properly work because phone)
if anyone here is fine with Android 8 then i can reccomend https://shop.shift.eco/shift5me as a small repairable phone with replaceable battery and headphone jack for like 200€.
The ressources are quite limited and it does not have NFC but if its just a phone for simple tasks it can be enough (check if your banking app supports Android 8!)