Termux is an Android terminal emulator and Linux environment app which can be installed directly w/o rooting. It comes with a minimal Linux base system and additional packages can be installed afterwards. The following script compiles and runs QuantLib in a Termux session
pkg install clang autoconf automake libtool boost-dev nano git git clone https://github.com/lballabio/quantlib.git cd quantlib ./autogen.sh ./configure --disable-static CXXFLAGS='-O2' CXX='clang++' make ./test-suite/quantlib-test-suite
HPC-QuantLib 
Great. Works on my son‘s S7. (Extension for the repo is git)
Test suite runs 38 min 59 sec on battery. Cmake build also works fine.
Thanks for the hint!