Links? Here :
iOS -
https://itunes.apple.com/ca/app/tekken/id1245078891?mt=8
Android -
https://play.google.com/store/apps/details?id=eu.bandainamcoent.tekkenmobile
*Note: I don't think this app is playable on rooted devices, but I might be wrong. So just give it a go. Also for Android devices, you need a minimum of v.4.4 API and preferably above 1GB of RAM.
The game contains, story mode, dojo challange (PVP Online), and live event (daily, weekly, monthly, and special). The AI range from very dumb to extreme (4 difficulty levels), but you'll need to complete each chapter before getting to unlock the more intelligent ones. The Dojo is unlocked once you reach lvl.4 in the Story mode. The live event is unlocked once you reach lvl.3 in story mode. Each time you win a set (+/-5 straight wins), you earn items such as a random character shard (which you must collect a certain amount in order to unlock a new character/costume), healing item, element shards, coins (to buy boxes), and gems (rarely acquired - also to buy boxes). You can purchase gems through micro-transaction (need to spend real money).
In the story mode, you bring 3 characters into battle, and you get to decide which of those 3 to use against the current opponent. Characters can be healed in 2 manners; 1. use the healing item, and 2. by not using it in your team. If you leave the characters untouched, it will auto heal itself very slowly. If not mistaken, each chapter are divided into 5 parts, and each parts you need to win 5 rounds, in order to unlock the next chapter. Each character has their own ability cards which continuously auto recharges during the fight. Also each character has it's own element; fire, earth, water, and lightning.
Once you have access to the DOJO, you get to play against your friend and players from around the world. Essentially, you get to send 3 characters to another player's dojo, or you assign 3 characters to secure your dojo from raids. Winning will earn you a dojo key to acquire items/enhancements. While the live event will make you do certain challenge in order to receive a special reward.
You can spend element shards on more WAZA cards for your favourite characters, and spend skill points to increase their ability. Also you earn extra rewards for levelling up; e.g. unlock secret characters , coins, and gems. Note that if your character is K.O.-ed, it won't auto heal, as such you need to spend gem to revive it to 1HP, and then need to spend on healing item or let it auto heal slowly.