Memory Analyse Tool(MAT)
1: export .hprof file
ADT>DDMS>Dump HPROF file
2: convert to standard format
use HPROF Converter tool provided in android sdk.
The hprof-conv tool converts the HPROF file that is generated by the Android SDK tools to a standard format so you can view the file in a profiling tool of your choice.
hprof-conv <infile> <outfile>
More at HPROF Converter
3:use MAT to open <outfile>