What exact engine is running on your dad's Dell? Maybe the Droidfish author has somehow restricted the nps for some reason. You really should mention the exact chipsets for both pieces of hardware.
Maybe a better comparison would be to go to the Stockfish web site and download the Stockfish 5 for Windows and Android binaries, and run them in console mode, then run the bench command. It'll give the number of NPS on one core, then you can directly compare the Dell vs. the Galaxy.
i have a samsung galaxy tab 4 10.1 inch and it has a 1.2 ghz quadcore with 1.5 gigs of ram. my dad has a dell laptop with a 2 ghz quad core and 4 gigs of ram. the difference in nps? well my samsung gets 400 to 600 thousand and my dads dell gets 2.5 million to 3 million. we are talking about a diference of 800 mhz and 2.5 gigs of ram. and his is a work laptop that has poorly designed company apps that run in the background constantly. any ideas?