IOS app crashes on iPhone 5

Question

I am writing an IOS app. It involves a lot of data downloading which involves images and text in JSON format. I am using NSOperation Queue to make the download process sequential. The entire app works fine in iPhone4 and iPhone4s but in iPhone 5 the app crashes while inserting data in to the database. I have an API call which returns about 350 items back. WHile inserting these records to database the app crashes.

I am not getting any crash logs while debugging. The app simply quits. But from device logs within the Organizer it shows Memory warning. MyApp is the name of my application.

Dec  3 17:14:21 Gavs-iPhone MyApp[6673] <Warning>: Inserted Reward

Dec  3 17:14:21 Gavs-iPhone MobileMail[6648] <Warning>: Received memory warning.
Dec  3 17:14:22 Gavs-iPhone MyApp[6673] <Warning>: Inserted Reward
Dec  3 17:14:22 Gavs-iPhone UserEventAgent[14] <Notice>: jetsam: kernel termination snapshot being created

Within device Console I can see this

Processes
     Name                    <UUID>                       rpages       recent_max   fds      [reason]          (state)

         keybagd <03955fb37478382481fc34df706700a1>          233              233  100   [vm-pageshortage]  (daemon) (idle)
   wirelessproxd <b5a0169c073b3fa7a2e63079774626bc>           97               97  100   [vm-pageshortage]  (daemon) (idle)
      MobileMail <759a544834f73ebfb26a73e4c16a71d6>          987              987  100   [vm-pageshortage]  (resume) (continuous)
            tccd <96df95e7143c3cdba0e4ce226d849f14>          148              148  100   [vm-pageshortage]  (daemon)
          MyApp <aa954e20bdf13ecf9fa250862caf480e>         6296             7314  100   [vm-pageshortage]  (frontmost) (resume)

What confuses me is this happens only on iPhone5. All devices runs on IOS 7.0.4 .

Is iPhone 5 allocating lesser memory compared to previous models? To add NSZoombies is not enabled.

Whats going wrong here?

Thanks