The HM101 wouldn't help your phone at all, but there is nothing you can do to help your phone quality besides replacing it with another portable music player, try the clip+ from Sansa. That will get you settled for portable use and get the HM101 for laptop use. Do not buy an amp unless you specifically want the music louder, head-fiers overrate amps. You just need a good DAC to get the most out of your Shures, and the Clip+ is a good DAC and a HM-101 is a good DAC, even spending $1000 on a DAC will net you only small improvements over your Clip or HM101, spending more is overrated.
You know, I've actually been fairly pleased with the quality on my phone. It has an Ericsson DAC and combined with PowerMP, it sounds at least as good as my old ipod touch (currently sitting in unused in my dresser drawer. I'm not sure that I want to shell out some money for the joy of carrying around a 2nd device if the sound improvements are only going to be minimal.
As for my laptop, though, I'm consistently less pleased with the sound which is sad considering I listen to nothing but FLAC on my laptop and nothing but mp3s on my phone. So, the external DAC appeals to me. I'm currently looking at the HM101 and E7 so I definitely appreciate the suggestion.