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+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.
+