iPhone flight tracking

Before buying an iPhone flight-tracking app, I thought I should check
out where the top apps get their flight data and learn which source
has the most accurate data.

At their web site ( http://www.mobiata.com/flighttrack ), I learned
that the leading app, FlightTrack, gets data from FlightStats. I
googled FlightStats and found 1,570,000 hits, with lots of praise for
its data.

Flight Tracker ( http://www.splashdata.com/splashtravel/flights/ ) is
cheaper that FlightTrack, but their web site does not give their data
source, so I wrote to their support email address. They responded:

Our Flight Tracker data comes from a 3rd party flight data
service, know as Custom Online Services.

I googled "Custom Online Services" and found nothing! So, I wrote
Flight Tracker again and inquired further. Their response:

It's a private 3rd party service. It's not for public
access - just developer services.

What do you think: Am I gullible to thing that "Custom Online
Services" is "private" and "not for public access" and is thus listed
nowhere on the web? Or is "Custom Online Services" simply fictitious?

P.S. Sure, I could just buy both apps, but am now curious about this
possible subterfuge. Or am I just being suspicious?