To answer several comments who suggest to use Free software:
You can't run GPLed software on iOS. The App store has its own license with term incompatible with the "no other restrictions" of the GPL, and Apple, who is the distributor, is not willing to provide the source anyway.
This means No FreeDos, no Linux, no DOSBox, no QEMU(which is has no interpreter, only a dynamic compiler, which also rules it out), no BOCHS...
I don't think that there are non-native, non-GPL, non-proprietary solution to run TeX on iOS.
To run TeX on iOS, you'd have to port the WEB/Pascal compiler (the language in which TeX is written) to ARM+iOS...
You can't run GPLed software on iOS. The App store has its own license with term incompatible with the "no other restrictions" of the GPL, and Apple, who is the distributor, is not willing to provide the source anyway.
This means No FreeDos, no Linux, no DOSBox, no QEMU(which is has no interpreter, only a dynamic compiler, which also rules it out), no BOCHS...
I don't think that there are non-native, non-GPL, non-proprietary solution to run TeX on iOS.
To run TeX on iOS, you'd have to port the WEB/Pascal compiler (the language in which TeX is written) to ARM+iOS...