Now that T-Mobile is selling the first Android phone, Google (NSDQ: GOOG) provided an update today on how developers can sell apps on the phone through the Android Market. Today, 50 applications are available, but starting Monday the floodgates will open, according to a post on the Android Developers Blog. Google said developers will have to register and pay a one-time $25 application fee in order to upload their applications to the storefront. In perhaps the most relaxed rules in the industry, once the developer is registered, the apps are available to users without further validation and approval. For now, only free applications can be distributed, but starting early next year, developers will be able to charge for applications. Google says developers will be able to keep 70 percent of the revenue, and the remaining amount goes to carriers and billing settlement fees. Most interesting to note, Google does not take a percentage. This is completely backwards from what Apple (NSDQ: AAPL) does today, which gives developers 70 percent and keeps 30 percent for themselves. Over and over, people have pondered what a carrier’s incentive will be to adopt the Android platform, well, folks, here’s your answer. Google explains: “We believe this revenue model creates a fair and positive experience for users, developers, and carriers.” Of course, Google is hoping to capitalize on the growing mobile advertising opportunity on the phone.

Of the 50 applications, not many of them today are big names, but there’s a few. For example: there’s mobile banking from Bank of America; MySpace, Shazam, BreadCrumbz, Buzzd and The Weather Channel. There’s also a number of mobile games, including Bubble Bash from Gameloft (EPA: GFT), Brain Genius Deluxe and Bonsai Blast from Glu Mobile (NSDQ: GLUU), and something new I noticed today was an app from T-Mobile that allows you to connect to all of its HotSpots for free.