Here are some instructions to enable 3G access with your smartphone.
Mobifone actually has quite decent information in English, here:
Here is a quick guide:
- Send SET DATA to 999 to set up the APN (in some phones, this is not necessary because it's automatically configured).
- Send DATA ON to 999 to register for data services.
- By default, you get package M0, which is "pay-as-you-go".
If you want to use a different package, you need to register for the package.
An interesting package is MIU, with flat rate of 50.000vnd/month. You get high speed for the first 600MB per month, and after that, your internet speed drops down to "normal speed" (whatever it means). To use it, send DK MIU to 999.
In most cases, you will receive a message asking you to confirm. If you do, send Y to 999 to confirm the package.
- To check the status of your package, send KT DATA to 999.
You can find the latest information on available packages and fees in the link above, under "Tariff".