Usually a high user interest into a mobile platform is guaranteed to bring about a host of tweaks and modding.
The first and most obvious opportunity for developers is the presence of a capacitive touchscreen that lacks multi-touch support. The reason why Google didn't implement multi-touch is still unclear, but rumors point to Apple as the main obstacle.
Anyway, whether it's coming officially or not is hardly the big question here, but rather when the eager Android fan coders will create a hack for it. The process has started and the first results were seen a month ago, available for anyone to try.
You will find the required files and instructions to open up your G1 to multi-touch here. The mod adds active multi-touch support for the G1's web browser and showcases how would multi-touch feel in Google Maps and the image gallery.
We tried this multi-touch addition for the web browser and it worked perfectly fine. The experience is quite iPhone-like and works like a charm.
Another interesting mod is the DroidSans Tweak Tools. It gives you the option to turn on the auto screen rotation, which lacks by default. There are some limitations of course, mostly with unsupported apps such as the web browser or unsupported software. More information is available at the link above.
Another disappointment was the missing virtual QWERTY keyboard. It is available in some third-party applications. Soon all Android owners should be able to get the official on-screen keyboard in the massive Cupcake update in April.
The upcoming Cupcake update will add video recording too. Video recording is something that the iPhone still lacks - even after two major OS revisions.
In December Google released a SIM-unlocked developer version of the T-Mobile G1 with unlocked boot loader. Today the dev tools can be found all over the web providing you with the ability to flash your device with different and modified firmwares, that come with some relatively useful apps for system monitoring and etc.
As we already mentioned internet tethering via USB is not available by default on the G1. The Tetherbot app is what you need for connecting your laptop to the internet using EDGE, 3G or whatever else your T-Mobile G1 is using. Here you can find the download package, detailed installation instructions and settings.
The obvious Bluetooth features absence will be fixed too with the upcoming update adding a Stereo Bluetooth support. If there will be more is still unclear at this stage.
There are plenty of other small apps tweaking many aspects of the OS, but none of them are quite as interesting as the ones we mentioned above so we won't cover them here. When Cupcake is released, be sure we will take a closer look at it.
The T-Mobile G1 is a full-blooded smartphone but surprisingly doesn't sport a document viewer - a must for a device in this class (not to mention the price range).
Yes, mail attachments such as office documents and PDF files are displayed but you can't download them and files saved on the memory card or in the phone's inbuilt memory can't be viewed either. Luckily, news of upcoming (paid) document viewers is circulating on the web, so we won't have too long to wait to see one working on a T-Mobile G1.
Having said all that, we can proceed happily as all the other elements of the organizer are ship shape.
Like the calendar, for instance. It has five different types of view - agenda, daily, weekly, monthly and today. Adding a new event is easy and quick, and you can also set an alarm to remind you about it.
There is also a calculator aboard and you can use it with either on the touchscreen or with the hardware keyboard.
We didn't find a preloaded voice recorder but it took us less than a minute to download a free and functional one at the Android Market. It even gives you the option to send the voice message right after it's been recorded.
Finally, The T-Mobile G1 features a decent alarm clock application which allows a huge number of alarms to be set, each with its own start time and repeat pattern.