Just two weeks after its Un-carrier 3.0 moves, T-Mobile US brings up Tablets Un-leashed, a free data service for life. T-Mobile will offer tablet owners up to 200 MB of free 4G LTE data every month for as long as they own their tablet, even if they're not yet a T-Mobile customer.

If you need even more data T-Mobile is offering a range of options - with no annual service contracts and no data overages. T-Mobile offers daily, weekly and monthly options for adding 4G LTE data. For T-Mobile voice customers, 'always-on' tablet plans start at $10 a month for unlimited data including 500 MB of 4G LTE data each month. You can add even more 4G LTE data in 2 GB increments for $10 more per month. If you would rather want to have the flexibility of on-demand data, T-Mobile offers daily and weekly passes. Daily passes include unlimited data with 500 MB of 4G LTE data starting at $5. The weekly passes include unlimited data with 1 GB of 4G LTE data for $10.

T-Mobile today also announced plans to extend its existing smartphone trade-in program to tablets. Beginning Nov. 1, anyone with a qualifying tablet can bring it into a participating T-Mobile store - even if it's only Wi-Fi capable - and receive a discount on a new tablet. Tablets in T-Mobile's portfolio will include the 7-inch Google Nexus 7 and the Samsung Galaxy Tab 2 10.1.

At rival AT&T, monthly plans start at $15 for 250 megabytes. The company also recently introduced $5 day passes.