XDA-Developers member jessetbenton has developed a great tool for Android OS application developers using a Mac. This is a droplet application that will auto-sign any dropped .apk and .zip files for Android OS, hence saving some real amount of time and effort for theme designers and/or modders working on a Mac.
Usage is very simple, as this is a droplet tool. Just drop the file you want to get signed on the application itself, and a new file ending with –signed will be created. However, you need a particular file, testsign.jar, to be present in your root directory. Follow the original thread link below for download and complete installation instructions.
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