I want to start develop mobile applications and sell it. There are many mobile platforms for which I can begin develop: Windows Mobile , Android, Iphone, Linux based Devices. I want to find out from people who has such experience which platform more comfortable and more profitible for me to use.
I would recommend Android as it's a growing market. Android development is well documented and newbie-friendly.
You may find these threads useful too:
http://stackoverflow.com/questions/1092144/what-mobile-platform-should-i-start-learning
http://stackoverflow.com/questions/598252/most-promising-mobile-platforms
http://stackoverflow.com/questions/1319704/getting-started-with-mobile-development
There is no general advice on this.
The recommendation clearly depends on your experience and several other factors. What programming languages do you know? What kind of applications do you want to develop? Do you want to take the risk that your software isn't even put in the corresponding app-store (see apple)?
You have to take several things into consideration. I'll try to make a short overview:
Android:
- needs Android SDK
- Java as programming language
- free marketplace (i.e. no prior control whether your app comes in)
- develop on any system you want to
- open plattform
- furhter information
iPhone
- needs iPhone SDK
- Objective-C as programming language
- prior evalutation of your app before storing it in the app-store
- you need to have a mac in order to develop for iPhone
- closed plattform
- further information
Windows Mobile
- developing with .Net-Framework
- don't know a lot more about it, but further information can be found here
Other Linux-based devices
- take a look at their specifications, they often have an own SDK
Also don't forget about Symbian for Nokia. They recently launched their OVI-Store. And oh, also Palm could become very interesting just after yesterday's news that HP bought it. It's also a nice plattform.
Which one of these is more profitable for you also depends on your skills. Good software will sell good, no matter which plattform you decide for. My recommendation clearly is: Take a look at the SDKs and the needed environments and then compare it with your skills. If you say, you have a good experience in Java development go ahead with android. If you want to do some mac-stuff choose the iPhone.
I'd say the markets with the highes potential clearly are the iPhone and Android markets. I don't know, how Palm will develop now but there could be a big potential in it in half a year or a year.
You didn't mention webOS in your original question, but it's worth a look. Has an open development model, like Android, but is based on HTML and JavaScript, so might be easier to get started with if you have experience in Web development.
Currently, the most lucrative platform is the iPhone. The Android is not even close yet. The number #1 selling game on Android is Robo Defense, its entry in the Market says 50,000 to 250,000 downloads, and its price is $2.99. Assuming the price has been constant, that means the developer has roughly made between $100,000 and $500,000 (after the 30% commission has been taken out). And yet, I have developer friends on the iPhone that have made way more money than that, and those friends are not even close to have the best selling apps on the iPhone in their own category.
Part of the problem is the number of handsets out there, according to Gartner, the number of Android handsets won't overtake iPhone handsets till 2012. The second problem is conversion rates, according to Admob, Android users are only worth 60% of the iPhone users in terms of converting from free lite version applications to paid applications (supposedly, Admob has compared identical apps on both Marketplaces).
That conversion rate is believed to be attributed to two factors, the type of users Android has, and the fact that Android currently only uses Google Checkout for its Market transactions (when in fact, it probably should use Pay Pal, not Google Checkout). But that too, should change soon. With the Evvo (from Sprint) coming out, Android will be on the very best phone, and with it, it will start attracting some of the very top high end users. Also, the Android Market is starting to accept transactions using carriers as go-betweens, so that should help remove some of the steps that it takes an Android user from buying an app (at least, I hope that it will).
And do notice that I didn't even mention the Ovi store from Nokia. The Nokia sdks are still as fragmented as ever. The Ovi store is currently a mess. Its three-star rating system is useless. All apps average to two stars. They don't allow you to upload screenshots. And the Ovi store is so expensive to upload an app to, $50 for Ovi + $150 in certificate signing fees, that it doesn't encourage new developers to even try it out.
Also, I didn't mention Microsoft. Microsoft is a bit of wild card right now. I can't say much about it, except that LG who was supposed to have more Windows Mobile phones than anything else now has more Android Mobile phones than anything else. So Microsoft better get their ass into gear if they'd like to stay competitive in the Mobile arena.