It only takes a few minutes to setup and requires no advanced technical skills or knowledge to use. Speedify is also available in the AppStore.

Please check the updated system requirements on the download page. This includes iPhones 5S, 6 and later, as well as iPads of 5th generation and newer. Speedify works on all iOS and iPadOS devices starting with iOS 12 and later. It provides world-class encryption, without forcing you to sacrifice speed or reliability. You don’t have to do anything, and you most likely won’t even notice anything different is happening. It is equipped with auto failover so that if one connection goes down, it routes all the data through the existing connection until the lost connection is restored. Speedify runs in the background of your iPhone proactively monitoring the quality of your connections. What you get is increased bandwidth, which allows all of your apps to run faster. This means it uses your iPhone’s Wi-Fi and mobile data connections at the same time. The data is rapidly reassembled and encrypted on the server. If you're going to sign up to Astrill let me know and I'll send you a week's free trial - I get a month for free if you go on to sign up for a paid account.The Speedify protocol uses multiple parallel sockets to connect with the VPN server. That's what I've been doing for the last 6 months or so and it works absolutely fine. It's a 5 USD a month extra on top of the Astrill subscription. You would probably be better off just getting the 'home plan' when signing up for Astrill, which allows you to run Astrill on 5 devices simultaneously. They may have fixed it now, but last I heard it was unreliable at best. However, I've heard of a lot of reports that the Astrill DD-WRT doesn't really work that well, if at all in China. This means that anything connecting via that router will automatically be connected to the VPN.

As far as I know, there is a way to get Astrill installed on the router itself so long as the router is DD-WRT compatible and you've flashed it with DD-WRT. I didn't know that Astrill were actually selling routers themselves, which seems to be what you're implying in your post.

Att dsl astrill app router