For those wondering about the hardware: 16MB of RAM, 133MHz ARM9, and 33MHz ARM7. 256MB of internal storage.
In other words, it's comparable to an early 90s PC. The fact that it can run a browser, complete with JS support, seems nearly unbelievable these days.
Keep in mind, it used Opera Mini, so no actual JS was run on the device. It was rendered server side and an "image" (draw instructions, really) was essentially sent as a response.
This is incorrect - you can run base64 bookmarklets without network. It is running a highly stripped down version of Presto. Opera Mini did use 'server side rendering' while this is handled on the device.
Twitter’s mobile site, for instance, is looking pretty good.
That surprised me as I wondered just how much JS capabilities the browser has; then I realised that article was written in 2013, when Twitter was still relatively sane and not the bloated SPA it is today (yet the actual content being displayed is not much different from 10 years ago.)
In other words, it's comparable to an early 90s PC. The fact that it can run a browser, complete with JS support, seems nearly unbelievable these days.