Belong offers a unique service offering called mobile data banking, and if you’re clever, you can legitimately bank a large amount of data and end up paying not all that much for it.

The premise is simple. Each month, your unused data is banked provided that you pay for your mobile service on time each month.

How does this work? Here’s an example. If you receive 15GB each month, and only use 5GB, then the 10GB balance is banked for use the next month. However, it doesn’t expire in the next month; the total rolled over can be rolled over again, and so on, provided you pay on time.

Using this methodology, you can accumulate quite a lot (especially if you’re not a big data user), and it’s easier still if you’ve got two SIMs – e.g. one for your phone, and one for a USB modem.

The best bit? Once you’ve accumulated a mountain of data, you can drop your phone / data SIM plans to the lowest monthly amount, and retain access to your banked data. Just pay on time, and it’s yours until either (a) your data runs out, or (b) Belong ends the deal.

It’s not a bad idea, but it’s a slow burn; an Ausdroid reader told us about his accumulation of some 400GB to share between two plans. However, even at its most conservative, it would take many months to reach that amount. There might be better ways to accumulate data, but ultimately, Belong’s roll-over of monthly data is a welcome offering regardless of whether you intend to hoard or not.