You can absolutely run arbitrary binaries. The binary format for Android is an APK, but if you really meant a random arm binary you can run that as well just fine, android even natively has a terminal now.
And what do you mean "graphics primitives"? You have an abstraction layer, the same as you do on Linux. Like you ain't writing directly against a particular video card either , unless you write a kernel driver.
And what do you mean "graphics primitives"? You have an abstraction layer, the same as you do on Linux. Like you ain't writing directly against a particular video card either , unless you write a kernel driver.