Yes, you can like girls if you are mainly straight. There are many different levels of sexual organization actually, according to the Kinsey scale:
Rating Description
0 Exclusively heterosexual
1 Predominantly heterosexual, only incidentally homosexual
2 Predominantly heterosexual, but more than incidentally homosexual
3 Equally heterosexual and homosexual
4 Predominantly homosexual, but more than incidentally heterosexual
5 Predominantly homosexual, only incidentally heterosexual
6 Exclusively homosexual
X No socio-sexual contacts or reactions
More here if you are interested:
https://en.wikipedia.org/wiki/Kinsey_scale
As far as dating apps for aspies, I don't know of many but there is this one new dating site for people with ASD called SpectrumSingles.com.