Three open source products are aiming to reduce the barrier to entry for customers wishing to build native mobile applications using web development skills alone.  These products are PhoneGap, Rhomobile and Appcelerator’s Titanium Mobile.

I’ve covered PhoneGap in the past.  People’s Choice Winner at Web 2.0 Expo Launch Pad, PhoneGap is targeted at web developers with HTML, JavaScript and CSS skills who want to build device agnostic applications across the iPhone, Android and BlackBerry platforms.  PhoneGap currently supports access to GPS, vibration, accelerometer, sound and contacts.  PhoneGap is licensed under the MIT license.  Developers and companies can use PhoneGap for mobile applications that are free, commercial, open source, or any combination thereof.

Rhomobile, selected Best Startup at INTEROP 2009, lets developers use HTML and Ruby to create native iPhone, BlackBerry, Windows Mobile, Symbian and Android applications.  Rhomobile currently supports GPS, contacts and camera functionality with plans to add SMS, push, audio/video capture and accelerometer support.  Rhomobile is licensed under the GPLv3.  This means you’ll have to open source your mobile application when it’s ready to be distributed, or pay for a commercial Rhomobile license.

Today, Appcelerator announced support for building native iPhone and Android applications using JavaScript, HTML and CSS with its Titanium mobile product.  Titanium mobile provides native access to the device’s storage, multimedia, input, and geo-location APIs.  Titanium is licensed under the Apache Public License V2.  Developers and companies can use Titanium for mobile applications that are free, commercial, open source, or any combination thereof.  BTW, if you’re at WWDC, Appcelerator is hosting a beta launch party from 6 to 9 PM at Jillian’s in San Francisco on Tuesday, June 9, 2009.

Rhomobile is the odd man out with a license that forces developers and companies to pay for a license or open source their own mobile application.  Unless Rhomobile delivers an order of magnitude more productivity than Titanium or PhoneGap, I foresee Rhomobile facing challenges with developer adoption.
The GPL works fine with developers, ISVs and partners when the majority of open source competitors are also using the GPL.  But in the face two competitors using liberal BSD-based licenses, the GPL is definitely a hindrance to developer adoption.  And I’d argue that developer adoption today will differentiate between leaders and also rans in 12 to 18 months.

Have you used any of these products?  What do you think?

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