The biggest filing problem I face is lack of online access when you most desperately need it
That one will keep popping up... I have some notes
here. Nothing particularly new there. Abroad, it's a toss-up between paying the roaming rate (which usually works but can be very pricey outside the EU), and buying a local data SIM.
One of the great features of EuroFPL is the ability (on the paid up membership version) to use SMS to delay a flight plan.
I used to have issues with EuroFPL refusing to accept certain (valid) routings and destinations.
That's curious. For IFR flight plan filing purposes, it is just a gateway to the AFTN. One recent problem I had, unresolved, was probably caused by some spurious character in one of the flight plan data fields. I retyped them all (or thought I did) but it didn't help, so out came Afpex, on my trusty winXP laptop, which on trips I keep
hibernated with the Afpex app loaded so I don't get the suprise download. Afpex does have the perverse advantage that it "just works", and I quite like seeing the ACK or REJ come back within a few seconds.