Here is the thing people don't know about the Android Market.
Android Market is for OHA as in Open Handset Alliance members only. The maker has to join the OHA to get the Market.
Second, the device must pass through a strict hardware and software compatibility suite of tests. If a device doesn't get the Android Market, there is a good chance Android Market apps will fail on it.
These rigorous procedures is the reason it holds the Android ecosystem together and prevents it from truly fragmenting.
While the big Chinese and Taiwan companies like HTC, Acer, Huawei, ZTE, Lenovo might be OHA members, all the smaller companies, which often make the tablets, are not. Plus the tablets may not conform to the Android Market requirements, such as having a built in GPS and gyroscopic compass on the device.
Another issue is that when before you install an Android application, do you notice it has all these requirements you need to see before you download? A requirement that I see often is the apps looks for a "phone state". Unfortunately a tablet is not a phone and therefore has no "phone state". Thus the app may likely fail on the tablet. That is the reason why Android tablets that do have the Market are in fact, technically, phones.
Might not seem like it, but by not having the Android Market on your tablet, you're saving yourself some potential headaches.
That is why Amazon is motivated to create its own Android app store. Same with Motorola, Same with Verizon. Same with HTC and Samsung. All these app stores bypass the Android Market's stringent restrictions can be used to serve non phone Androids. Archos has its own store too.
There are some places where you can already download Android apps from web pages. A good example is Getjar. Some websites have direct downloads too. If you hit the Twitter mobiel site with an Android browser, the page offers you a link to directly download Twitter for Android into your tablet.
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