This is an amazing smartphone, that is let down mostly by its hardware capabilites.

The Tmobile g1 is the first Android powered phone, and features almost everything that the Android system has to offer. Or at least, it did. With the introduction of the new 2.0+ system, the G1 has been left in the dust on 1.6. This is fine, until you realize you can't use features such as installing applications to your SD card.

Features;

Android 1.6 operating system, 3 inch touchscreen (multi-touch is implemented but not supported), QWERTY keyboard.

The android system is great, and is basically what makes this phone what it is. I could go into detail with how good it is, but basically it is one of the top 3 contenders for smartphone users, the other 2 being blackberry and iPhone.
The phones hardware is what lets it down, with limited phone memory often the system can become laggy and run slowly. Using an app like taskiller can stop this, but then you have to waste time opening the app.
The memory also limits how many apps you can install, and with only 80mb set aside for this, you will soon find that you cannot have every single app installed at once. This is made even worse by the fact that Android 2.0+ has installation to SD card support, but the G1 has not been updated to this yet.

Sound quality

The quality of the speaker and mic is very good, and I have never had any problems with these.

Construction;

The phone is built like a rock! Mine has been thrown at a fireplace, dropped many times and is still going with only a few scratches to show for it. You will definitely need to buy a screen cover, but then, which touchscreen phone doesn't need one.