There are a variety of ways to deposit money to play mobile slots:

Phone Bill: Deposit using your phone bill by charging to your airtime credit.

Credit / Debit Card: Register a card within mobile slot games and away you go.

Ukash: Also known as electronic cash, buy a voucher from a shop and enter into your slot game.

In addition, some mobile casinos may let you deposit using Click2Play and Neteller amongst others.

Read more about banking.