I use a xapo because its easy to make a transaction
For correction, Xapo is not a mobile wallet its a web wallet, and to OP I must suggest Mycelium is one of the most recommended mobile wallet here (aiOS/Android) just make sure you make a backup your phrase to make sure your funds are safe.and if you want to trade with altcoins there are many multi wallet there like exodus but its a desktop but coinomi supports mobile also.