There’s an entire ecosystem of Facebook-tier repetitive browser games that are designed to keep you tapping for hours as you chase tokens you can exchange for AE coins or coupons. Actually, the main point is to get you to make impulse buys from within the games themselves
The games all use different tokens and naturally run on slowly regenerating energy. If you run out energy, you can get more by exchanging some of your coins or tokens, browsing products on AE, opening another game, or by ordering something for a large energy boost
Simply buying stuff normally on AliExpress doesn’t give you game tokens or energy, you need to directly buy an item from a listing the game shows you for it to count
Every single game also has a battlepass type deal with dailies and weeklies to complete for even more tokens
All of this started when Halo 2 introduced XP into online shooters 
There’s no countdown on the AE minigames, but yeah, most of the times you have to buy something from a selection of random crap they show you
Also, when the games ask you to browse items for 30 seconds for more energy or whatever, the app will often just stop you when you’re scrolling and tell you to click on a specific random item, which you don’t want to do because it fucks your recommendations and personalised deals elsewhere if it’s something you have no interest in