Once hardware keyboards standardized around ASCII in the '70s, it cramped the promise of APL's custom notation. On touchscreen it's trivial to render a software keyboard that contains the entire symbol set (perhaps even adapted to the user's experience level to make it less scary initially?). Increased resolution could be used to make the programs easier to parse visually by e.g. scaling symbols based on their context and nesting level, just like we do in math equations.
I'd like to work on an open source APL variant that runs on iPad and/or touchscreen Windows. It should be aimed at entry-level programmers because they don't have the imperative mindset strongly ingrained yet. It would be interesting to see if "touch APL as first language" could be a viable approach to teaching programming. Just need to find the time somehow... :/