[Amanieu]

When ARM released AArch64, it was a completely new instruction set rather than an extension of the existing 32-bit ISA (like x86-64). AArch64 is a much better designed ISA than AArch32 and supporting both in hardware effectively doubles the complexity of the instruction decoder, so it was clear that eventually there would be AArch64-only CPUs (as there are today).

The technology behind Tango started as a research project while I was doing my PhD. After finishing my dissertation in 2016, I looked into opportunities to commercialize it by contacting every company that was building or planning to build an AArch64-only CPU. There are sufficiently few that it is easily doable even for a small company.

Building a production-ready binary translator is technically challenging and requires a lot of work. The difficult parts are achieving high performance (Tango scores within 10% of native 32-bit execution on benchmarks), low latency (using AOT translation to accelerate startup times) and compatibility (Tango was tested against the top 1000 Android apps and works with all of them).

Already by 2017, Tango was capable of translating AArch32 Android applications. At that point it makes more sense for companies to license our technology rather than developing their own implementation from scratch.