People have been asking what web browser performance is like on a $7 dual-core A20. Here's an honest appraisal and some tips.
The first thing to bear in mind about the A20 is that it was a dual-core upgrade of Allwinner's first major success: a $7 processor from 2010 known as the A10. The A10 was designed as a "kitchen sink" tablet and IPTV processor, so it included HDMI, SATA, Ethernet, 24-pin camera interface, a 1080p60 hardware video decoding engine and much more. The A10 took the Shenzen Electronics Industry by storm with its $15 tablet BOM, and, thanks to its lower price, was extremely disruptive and even caused a minor recession. Any ODM and OEM holding large stock of alternative tablet and IPTV box design components rapidly went bankrupt as their clients recognized that the more expensive alternative products wouldn't sell, wrote off huge cash deposits and reneged en-masse on existing large-order contracts in order to back A10-based products instead. The low price and popularity of the A10 led many to research it and incorporate it in their projects. After several years of work by the sunxi community, we now have full GPL-compliant support for the entire boot process, 2D graphics, and 1080p60 video playback.
What the A20 doesn't have is "fantastically quick general-purpose performance". ARM processors achieve their low power by adding specialized hardware co-processors (video, crypto, etc.) and by increasing latency (such as by restricting DDR RAM data bus bandwidth to 32 or even 16 bit, where most Intel systems have 128, 256 or even 512 bit wide memory buses). You simply can't have both low latency and low power: it's a literal physical impossibility. So with that in mind, you know for a fact that running a modern desktop web browser on the latest modern top-used web sites simply isn't going to be fast. Instead, there are some things that can be done to get reasonable performance.
Third, the most annoying consumption of computer resources is advertising. Normally, on a standard intel-based modern desktop or laptop, adverts are reduced to merely being "frivolous" consumption of resources, but on a mobile low-power processor it becomes almost irresponsible of companies to develop web sites that make people's devices grind to an unusable halt. Until companies start acting responsibly, the solution is simple: install u-block.
Fourth: still under investigation but very close to success is the use of hardware-accelerated video plugins inside web browsers. Cedrus, the reverse-engineered hardware acceleration libraries, can be used successfully right now with mpv, mplayer and other VDPAU-compliant video players; for web browsers we need gstreamer, which in turn can use VAAPI or VDPAU for in-browser video playback. It's nearly there.
Lastly, remember that this is a modular upgradeable design, and that you're backing an idea: you're helping us to change people's relationship with their computers to a positive one, and we're doing it on a responsible budget. You will be able to upgrade.