It is an idea of a virtual wallet to use your cellphone for online and offline transitional uses. To have a mobile wallet certain amount must be pre- loaded to a wallet service provider. Then you can go to any establishment where the service is available. You can then pay via social media, text message or website. The transaction you can do with this service provider is almost limitless, from utility payments to E-tailing and offline payments almost all of your daily transaction.
What happens to the money you pre-loaded ?: 

Like any other banking system the mobile wallet also has complete guidelines check which takes full care of customer interest and queries. The company  creates an escrow account so that money can be debited by the user and when the users pay for his/her transaction then and then only is the money going to be credited to pay TM.
However, not all wallet types are required to escrow account therefore inquiry with the vendor  must be done before registering with one.

Your wallet can be snatched easily but your mobile wallet cannot but yes, there is a chance of your mobile to also be stolen. Secondly, if the bill amount is rs.326 or rs.427 then you wouldn’t worry about asking for change. With mobile wallet its a single tap transaction. Lastly, its much safer and faster than E-banking as E-banking exposes your bank data to the establishment during transaction while mobile wallet restricts exposing confidential information.

Only people who have speedy and dependable internet access can use this feature. There is also a limitation for transaction so most of the places you still need to use a card or cash. There is also a limit as to how much you can deposit as heavy payments is out of reach. As for the sustainability you never know when the battery life of a smartphone is going to die on you even for that one click.