I'm thinking of getting a MiFi device and connecting to the internet via a pre-pay data plan with someone like true.

I'm just wondering how you go about activating the plan of your choice for your sim card on a MiFi device as it doesn't have a keypad?

Anyone got and care to share how they work?

Thanks.

Dependent on the Network(certainly with AIS), you can top up online(using a voucher code) and then apply the package.

If you do not have a phone, with which you might manage your SIM (including subscribing to mobile data packages), you may be able to manage it via a MiFi UI, say if purchased directly from TrueMove H, or via their iService web-based platform (requires registration).

If you have a True sim and have your computer's Internet from the mifi you can go to this website and buy your packages...

http://hlife.truecorp.co.th

Thanks for the replies. That answers my question.

Edited to add: some 3G devices can originate USSD commands, I have a D-Link DWM156 USB aircard which supports this capability, although it did require a firmware update to add that feature.

USSD commands can be used to "manage" an account, including originating subscription codes like *900*3339# Send (TrueMove H Net 399), and checking usage/balance/expiry.

http://truemoveh.truecorp.co.th/3g/toppings/iplay/entry/654