Ask HN: What's the most memorable un-updated app in your app purchases?

Currently in a bout of sleeplessness and I started going through my iOS app purchase history and noticed some gems that I no longer use due to lack of updates. My most memorable is Things 2, and because I use an iPhone SE, it doesn't look outdated at all. While glorifying the past, I thought it would be interesting to hear what other community members used to cherish but had to move on from!