There are so many ways Activision could've meddled with Tencent's mobile version of Call of Duty. So many ways it could've been a microtransaction, recurrent spending-filled mess, filled to the brim with ways to extract as much money out of you as possible - but it's not.
Thankfully, Call of Duty Mobile is 100% exactly what it needs to be. A COD on the go, replete with multiplayer, tight progression systems, a mishmash of characters and maps from all the games, plus a battle royale mode for good measure. It's even getting Zombies in a future update, and all for free.
Now, I don't doubt Activision WILL load this full of nefarious additional purchases, breaking game loops and emphasising grind (they certainly did with CTR and Black Ops 4), but for now, let's enjoy Call of Duty on your phone.
PUBG Mobile, Tencent's other major project, was a similar case of "Yup, this SOMEHOW works" back in February 2018, and with COD Mobile, they've seemingly pulled off the impossible yet again.
Needless to say, COD on the go feels brilliant, and to get the most out of it we'd best get to sharing as much advice as possible.