If you use any methods from the restricted API, you can't test the app on the device without signing it. In order to test it without signing it, you must remove all calls to restricted functionality. (The restricted functions are marked with a lock symbol in the JavaDoc).
Sometimes there are alternate functions you can use to replace a restricted function, but in most cases you'll probably have to sign the application. It really isn't that complicated to get the signing credentials, and you'll need them if you intend to sell your app.