Samsung made an early Mobile World Congress appearance to show off the Galaxy S Blaze 4G, and HTC announced the One S, both coming to T-Mobile in the next couple months. Neither have a specific release date, but the Galaxy S Blaze 4G will cost $150 on contract and is reported to go on sale in late March.

While it lacks the large 4.3-inch screen size of the One S, the Galaxy S Blaze 4G will probably be a bit less expensive. That's because the One S is the successor to the Amaze 4G, and that phone is $230 on contract. Once the One S comes out, T-Mobile may drop the price of the Amaze 4G, but that is certainly no guarantee.

HTC's One S features a 960x540p resolution qHD Super AMOLED display, dual cameras, Android 4.0, 16 gigabytes of storage, full gigabyte of memory, super-thin 7.9 mm body and HTC's brand new Sense 4.0 software overlay. While there is no expandable memory slot, Sense 4.0 includes a free two year subscription to Dropbox, and that includes 25 gigabytes of storage. Sense 4.0 also includes new camera features and deeper Beats Audio integration. Any games or music apps will be allowed to use Beats audio instead of only the usual HTC Music app.

Furthermore, because One S ships with Android 4.0 on board, there are new browser and homescreen features, along with the ability to check on your data usage to avoid overage fees. Samsung's Galaxy S Blaze 4G will ship with Android 2.3, and there is no timetable for when it will get upgraded. Galaxy S Blaze features a 3.7-inch screen with an 800x480p resolution Super AMOLED display, 16 gigabytes of storage, microSD card reader and dual cameras. Depending on what price the One S debuts at, these two might be attractive to T-Mobile customers ready to upgrade. A side-by-side comparison wouldn't hurt, though the One S is the more impressive device at a glance.

Tell us in the comments if you think HTC and Samsung have made a worthy effort with these devices and if you'd be inclined to give either a look when they arrive.