The Galaxy S shipped with only 256 megs and a single core. It was a capable device at the time, although it can barely run any modern apps. I know this because I replaced mine only a month ago. As recently as 6 months ago it would run Spotify and Runkeeper simultaneously, though with recent versions of Spotify I lost the ability to multitask while not on Wifi. On Uber the only things preventing me using it were the custom text fields, which wouldn't allow me to key data in properly. The biggest memory hogs were recent versions of Google Play at 40 megabytes of ram, so I would keep the Google services downgraded unless I needed to install an app.

The base Android system will run with surprisingly little RAM.