I mostly play on my phone while commuting into London. Can anyone recommend a site that is fully optimised for mobile? I don't want to download another app that takes up storage; just a browser-based site that actually works smoothly.

For mobile gaming without the hassle of an app, Amazon Slots is a solid choice. I play on my Android during my lunch breaks and it runs perfectly in Chrome. The site is fully responsive, so the menus and games resize automatically to fit your screen. It’s very snappy and I haven’t experienced any crashes or lag, which is rare these days. It’s definitely designed with mobile players in mind first.