Radical Image Optimization Tool (RIOT) is a free image optimizer that will let you to visually adjust compression parameters.
JPEGmini
Commercial
JPEGmini is a photo optimization software.
PNGGauntlet
Free
PNGGauntlet is a PNG compression app for Windows.
OptiPNG
Open Source
OptiPNG is a PNG optimizer that recompresses image files to a smaller size, without losing any information.
Compare optimus.io with alternatives
Compare RIOT - Radical Image Optimization Tool and optimus.io and decide which is most suitable for you.
Compare PNGGauntlet and optimus.io and decide which is most suitable for you.
Compare JPEGmini and optimus.io and decide which is most suitable for you.