Here is a chart containing most of the games and app stores that I'm aware of in alphabetical order with scores from various categories. While I know that some of the entries aren't technically the traditional idea of app stores, I've added them specifically because you can use them to download games and apps and therefor can be used as alternatives to app stores. Some information might be wrong or outdated, I haven't used some of these platforms in years.
I should also mention that I use most of these websites with an ad blocker. If any of these websites have terrible ads and I haven't already mentioned it, please tell me so I can dock points from them.
Every time you see an asterisk (*) both in the charts and the lists at the bottom of the page, you can hover your mouse over the text to get an additional explaination.
| name | Supported Platforms* | App Discovery* | rating/reviewing apps* | Support* | Adult games* | Total Score |
| Amazon Appstore* | 0.5* | 0* | 0* | 0* | 0 | 0.5 |
| APKMirror | 1 | 0 | 1.5 | 3 | 0* | 5.5 |
| APKPure | 1 | 0 | 3 | 3 | 0* | 7 |
| Aptoide | 1 | 0 | 3 | 2 | 0* | 6 |
| Artix Game Launcher | 4 | 2.5* | 0 | 3 | 0 | 9.5 |
| Epic Games | 1 | 0 | 0* | 0 | 0* | 1 |
| F-Droid | 1 | 1* | 0 | 3 | 1* | 6 |
| Flathub | 3 | 1 | 0 | 3 | 1* | 8 |
| Gamejolt | 3.5* | 0 | 1.5 | 2 | 0 | 7 |
| Github | 4 | 3* | 2* | 2 | 0 | 11 |
| GOG | 3 | 3 | 3 | 3 | 1* | 13 |
| Google Play Store* | 1* | 3 | 3 | 0 | 0 | 7 |
| H-Game18* | 4 | 0 | 1.5 | 0.5* | 2 | 8 |
| IndieDB | 4 | 0 | 3 | 3 | 1* | 11 |
| IndieGala | 3 | 0 | 0* | 3 | 2 | 8 |
| Itchio | 4 | 3 | 3 | 1.5* | 1 | 12.5 |
| Microsoft Store* | 0 | 0 | 3 | 0 | 0 | 3 |
| Nutaku | 4 | 1.5* | 0 | 3 | 2 | 10.5 |
| OpenDesktop | 4* | 0 | 3 | 2 | 0 | 9 |
| Samsung Galaxy Store* | 0.5* | 0* | 3 | 1 | 0 | 4.5 |
| Snapcraft | 3 | 0 | 3* | 2 | 0 | 8 |
| SourceForge | 4 | 0 | 3 | 3 | 0 | 10 |
| Steam | 3 | 3 | 3 | 2 | 1.5* | 12.5 |
| Tentacle Games* | 2* | 2 | 0.5* | 0.5* | 2 | 7 |
| Uptodown | 1 | 0 | 3 | 3 | 0 | 7 |
| name | Supported Platforms* | App Discovery* | rating/reviewing apps* | Support* | Adult games* | Total Score |
| Freetogame | 2* | 3 | 1.5 | 3 | 0 | 9.5 |
| Gamefaqs | 4 | 1 | 3 | 3 | 1* | 12 |
| MobyGames | 4 | 2 | 3 | 3 | 2 | 14 |
| RAWG | 4 | 3 | 3 | 3 | 2 | 15 |
| TasteDive | 2* | 3 | 1 | 1 | 1* | 8 |
| name | Supported Platforms* | App Discovery* | rating/reviewing apps* | Support* | Adult games* | Total Score |
| Getjar | 2 | 0 | 0.5* | 1* | 0 | 3.5 |
| GX Games | 2 | 0 | 0 | 2 | 0 | 4 |
| swfchan | 2* | 1.5 | 0 | 3 | 2 | 8.5 |
| Tic80 | 2 | 0 | 1.5 | 3 | 1* | 7.5 |
The following is a list of websites I'm aware of but haven't gotten around to using them. Some of them aren't in english.
There are some additional places that I'm not going to provide above but I'll list them here to signify that I'm aware of them.