[bri3d]

Many cars have had externally reprogrammable ECUs since the mid 1990s (with lots being fully reverse engineered), but yet tuning is still relatively esoteric and generally very expensive.

What do you think has changed / will change that will lead to an onslaught of dangerous amateur tuning by phone? The technology to do so has existed for years.

[freehunter]

It exists in other motor vehicles. My last roommate had a quad where he would tune the ECU with software on his laptop depending on where he was riding and what parts he had installed.

[stolio]

Falling barriers. Like you say, tuning is currently very expensive. The financial and technical costs act as an idiot filter (forgive my negativity.) Those barriers are falling so we're left with artificial costs i.e. legal penalties and intentional code obfuscation.