You’re probably thinking, “what? How can that be? Android has to be the most open, it’s open source, right?”
And you’d be right… until you get into actual Android devices that are for sale. Other than the Google Dev Phone 1 (which has some other restrictions,) all of the devices are locked down at least somewhat.
There is one exception to my point – in one or two ways, Palm OS is more open than Windows Mobile. However, Palm OS is irrelevant nowadays, but I’ll include it in the comparison anyway.
So, here goes, a comparison between the major smartphone platforms, in terms of openness. Openness will be compared on the following metrics: openness of source code, ability to run unsigned applications without jailbreaking, difficulty of getting applications signed if needed, presence of a “kill switch” for applications, cost of developing for the platform, and ability to manipulate the device filesystem from a user perspective (not an application perspective.)
I’ll note that I’ll use worst case scenarios for difficulty of signing.
In the case of Android, I’m using real world implementations, not the Google Dev Phone, and not Android distros on phones that didn’t ship with it.
Palm OS
Source code: Closed
Unsigned apps: Allowed, no support for signed apps
Difficulty of signing apps: N/A
Kill switch: None
Cost of developing: Free (prc-tools)
Filesystem: Fully accessible
iPhone OS
Source code: Closed
Unsigned apps: Disallowed
Difficulty of signing apps: Difficult (all apps must go through inconsistent and restrictive approval process)
Kill switch: Yes
Cost of developing: $99 (SDK, more money for a Mac if you don’t already have one)
Filesystem: Inaccessible
Blackberry OS
Source code: Closed
Unsigned apps: Disallowed
Difficulty of signing apps: Easy (purchase a signing key from RIM one time)
Kill switch: No?
Cost of developing: $20 (signing key)
Filesystem: Restricted access (it’s also not actually a filesystem, but I digress)
Android
Source code: Open
Unsigned apps: Allowed, but not by default
Difficulty of signing apps: Easy?
Kill switch: Yes
Cost of developing: Free
Filesystem: Inaccessible
Symbian
Source code: Open
Unsigned apps: Disallowed (workaroundable, though)
Difficulty of signing apps: Self-signable for partial access, free rubberstamp for most access to one device, may be difficult (but documented) for full access
Kill switch: No?
Cost of developing: Free for self-signed, $20 for Symbian Signed Express, >$200 for Certified Signed, more for full access
Filesystem: Restricted access?
webOS
Source code: Partially open
Unsigned apps: Allowed through developer mode, normally signed apps required
Difficulty of signing apps: Unknown as of yet, should be easy to moderately easy
Kill switch: In development
Cost of developing: Free
Filesystem: Inaccessible?
Windows Mobile
Source code: Shared
Unsigned apps: Allowed (supports signed apps, some devices could theoretically require signed apps)
Difficulty of signing apps: Must purchase certificate from a CA, after that, easy
Kill switch: No
Cost of developing: Free for unsigned (although MS would prefer you buy VS,) $350 for Mobile2Market from Verisign (1 publisher ID, 10 content IDs) for signed, may be less from elsewhere
Filesystem: Fully accessible
If I’m wrong anywhere, let me know.
But, it is a sad, sad day when MS makes the most open OS in a field, and two of those OSes are Linux-based, and a third is open source.