Pixel Dungeon: Roguelike, infinitely replayable. https://play.google.com/store/apps/details?id=com.watabou.pixeldungeon

Auralux: A simple real time strategy game. https://play.google.com/store/apps/details?id=com.wardrumstudios.auralux

2048: Simple to learn, difficult to master puzzle. https://play.google.com/store/apps/details?id=com.androbros.puzzle2048eng

My Boy: A Game Boy Advance emulator (Game files, called ROMs, not included). https://play.google.com/store/apps/details?id=com.fastemulator.gba

If you also consider paid games that have no available purchases inside:

• Stardew Valley
• Alien Isolation
• Crypt of the NecroDancer
• Super Meat Boy Forever
• Terraria
• Layton series
• Witcheye
• World of Goo

There are plenty of ports or quality games on Android. They’re a minority, but plenty