If you'd like to keep your Apple specific dock, but be able to use it with your Android phones or other accessories, you could try getting a patch cable like they show in this article. It takes the Apple dock connector and channels just the audio pins to a standard 3.5mm headphone jack.
(The dock you own has to be a "universal" type that works across multiple devices and does not interface specifically/exclusively with the software or hardware of the Apple device)
Gottabemobile.com | How to Connect Your Android Phone to iOS Dock Accessories Revisited
The CableJive products seem to be a popular brand, though you might be able to find the same cable or another type of adapter for slightly cheaper. There are other such products out there.