[ogig]

I've used this site for quite some years now. Shameless plug: As someone struggling with ear training I created an app that tackles something that the usual suspects wont; the concept of been in tune or not: Probably worthless for trained musicians, but if you can't even tell if something is in tune, or why are 5th so used: https://intunetrainer.conpixel.es/

[vunderba]

Nice job. There's also a relatively well-known app called "TE Tuner" which I've used when helping my students become familiar with fretless instruments (such as the violin) specifically because it lets you visualize the sound you're playing at the cents level. I've found it can be quite helpful at the early stages of learning.