Signapk is a command line tool for signing ZIP files, including JARs, APKs, and Over-The-Air (OTA) updates, in a way compatible with Android's mincrypt verifier, using EC or RSA keys and SHA1 or SHA-256. The tool can additionally sign APKs using APK Signature Scheme v2. It is the standard tool used to sign APK and JAR files distributed as part of Android ROMs.