Developers have been hindered by the need to develop an app from scratch for each smartphone platform (for example, Apple's iPhone, Google Android, Windows Mobile, Palm webOS, and Nokia's Symbian). Because apps developed in the native language of one operating system aren't compatible with others, it's tough for users to have a consistent experience with an application: If you have an iPhone, and I have an Android phone, an app you suggest to me may not be available for Android, or it may work much differently. As Jason Calacanis pointed out on This Week in Startups, it's a shame that we spent so much time developing platform-independent standards for the Internet, but now we're back to fragmented platforms.
A blog post by Savio Rodrigues mentioned three cross-platform development tools; I learned of one more. Here, I've listed my impression of their features and drawbacks, but we haven't used them, so I'd like to get developers' impressions and experiences on them. I'm not a developer, so this is a high-level view from a business perspective.
It's from Nitobi Software, which doesn't charge anything for the software, but offers support plans from $1,000 - $25,000 per year; the pricier plans allow more developers to use the support. Nitobi offers PhoneGap training classes as well. There are also free community resources for PhoneGap, such as a Google Group and Wiki.
Again, there is a free community version; it includes analytics and a forum. Appcelerator support plans are available for $1,699-$4,499 per user per year. Titanium also offers Appcelerator University Training.
Appcelerator's big plusses are being able to code in web standards and getting native code out. So your app should be quick to develop (if you don't already know Objective C, for the iPhone; or Java, for Android) and run fast. Here's one coder's review of Appcelerator.
Rhodes lets you code in HTML and Ruby for iPhone, Android, BlackBerry, Symbian, and Windows Mobile. If you need backend syncing, RhoSync can handle that data exchange for you. If you want a hosted development environment, RhoHub is available.
You can use Rhodes for free, but only if you open-source your app. Otherwise, Rhodes costs $500 per app. RhoSync starts at $5,000 per app for up to 100 users, then the price doubles each time the number of users increases ten-fold. The RhoHub development environment is free for public apps and collaborators; it costs $20 per month for three private apps or $100 per month for 100 private apps. RhoMobile also offers training.
Rhomobile's major plus seems to be that there's a lot of infrastructure available if you want to use it, but you do have to pay for it. There is a free, no-frills version, but you have to open-source your code, which many developers may not be willing to do.
QuickConnect's code is open source, and you can use it for free whether you're developing open- or closed-source projects.
QuickConnect seems to be bare bones and a good choice for developers who want to be involved in the framework's development.
For a bootstrapped startup like ours, Appcelerator seems to offer the best combination of price (free if you don't need support) and speed (native speed) for key platforms (iPhone and Android). If you're a well-funded company that can pay more to get to market quicker, Rhomobile may be for you. PhoneGap sticks the closest to web-standards development -- there's no conversion to a native programming language -- but you may give up app speed to gain that convenience. And QuickConnect is small and lets you interact directly with its developer to request fixes and improvements, but doesn't have the backing of a company if you need extensive resources or support.
Do you have experience with any of these cross-platform development tools? Let us know what you've found!