sometimes a letter is two letters long

(this observation brought to you by the letters œthel and æsh, as found in words like onomatopœia or archæology)

there's also eth/eð and thorn/þorn and, well, "ch" is probably a dozen different letters and English Wikipedia doesn't give names for any of 'em, just pronunciations.

I mean, maybe esh has a name. eʃ? our phone's keyboard doesn't seem to show any sh symbols on a long-hold of the s key - maybe the IPA symbol is too modern for them to expect us to spell anything with it.