Refuse to believe whatever you want, but all you're doing is proving your ignorance. The DS does not have enough RAM to even come close to proper GBA emulation, and the processor that it runs in DS mode is not going to clock over 66mhz.
Your phone is likely at least 600mhz or more. So, of course your phone can run things that DS-mode homebrew cannot.
Either buy a DSTwo, or just suck it up and deal with it. Your disbelief isn't going to magically add more processor power to your 3DS, nor will it magically enable hardware that is incapable of emulating the GBA to do so.