Starting off, we should take a quick look at the AndroidManifest.xml through AXMLPrinter shows which is the main activity;
<activity android:label="@7F040001" android:name=".InsomniActivity">
Now we see what where to start our search without opening the app yet, toss that crackme into baksmali and get ready for the output. No baksmali tricks in place, so we can just take a look right at the main activity, InsomniActivity. The only interesting bits for us is the call to compute method on keyBytes and setting an onClick listener for the validate button;
read more at: InsomniDroid – crackme solution | strazzere.com.