zipalign -- zip archive alignment tool usage: zipalign [-f] [-v] <align> infile.zip outfile.zip -f : overwrite existing outfile.zip -v : verbose output <align> is in bytes, e.g. "4" provides 32-bit alignment infile.zip is an existing Zip archive outfile.zip will be created The purpose of zipalign is to ensure that all uncompressed data starts with a particular alignment relative to the start of the file. This allows those portions to be accessed directly with mmap() even if they contain binary data with alignment restrictions. Some data needs to be word-aligned for easy access, others might benefit from being page-aligned. The adjustment is made by altering the size of the "extra" field in the zip Local File Header sections. Existing data in the "extra" fields may be altered by this process. Compressed data isn't very useful until it's uncompressed, so there's no need to adjust its alignment. Alterations to the archive, such as renaming or deleting entries, will potentially disrupt the alignment of the modified entry and all later entries. Files added to an "aligned" archive will not be aligned. By default, zipalign will not overwrite an existing output file. With the "-f" flag, an existing file will be overwritten.