The recent update crashes the app on all BlueStacks (4, 5 and Pie). I can't believe the devs at that company. They don't seem to want people to use it on Android emulators. It reminds me what they did to the bigo.tv website, where most of the broadcasts no longer play even if the broadcaster is broadcasting. There is also weird jarbled graphics with some broadcasts and now the UI when you select the bullet screen... Source: over 1 year ago

I've tried a few, the best one was pingo (https://css-ig.net/pingo). Pingo -s9 gives better results than oxipng with Zopfli, while being usually two order of magnitudes faster. It's also faster than "regular" oxipng while being better. I can usually shave of 15%/20% of the size of png files I encounter. One thing I didn't check is that you might pay that in decoding time, I've never seen anybody talking about that... - Source: Hacker News / almost 2 years ago

Pinga, GUI for Pingo (https://css-ig.net/pingo) for lossless photo compression while keeping the metadata. Source: almost 3 years ago