Due to the Bandwidth requirements, your best options are

From the Android remote into a VPS or home PC
or
Just use an Exchange from the Android
(*This offers the most advantage , as their is no need to download the blockchain,
and it gives you the ability to perform Offchain Transactions if you want to use it for retail purchases.
Offchain Transactions can happen immediately and are more suitable for retail.
Cryptopia & NovaExchange provide Offchain services.*)