Here's the build info displayed for the mobile Gmail web app in Chrome. It's probably helpful for debugging the app and only available internally.
"Build At: grapebot@grapebot-cbf-9.cbf.corp.google.com:/usr/local/google/grape/grapebot/runner1_1/superpudu-client_Piper/google3
CL: 49089810
Build Label Verbose: superpudu_130708.00_p0"
Apparently, Grapebot is a bot used to build the Gmail app, while Superpudu is the codename for the mobile Gmail app. There's a list of features that are enabled, including HIGH_RESOLUTION, ACCOUNT_SWITCHER, ADS, SETTINGS_REDESIGN and more. Ads in the mobile Gmail?
Here's the build info for the Android-optimized mobile Gmail:
As you can see, the list of features is slightly different. You can find: GLOW_BUTTONS, STICKY_MENUS, ANY_ZOOMER, DOODLES, WEB_ATTACHMENTS and more.
Here's the build info for iOS. Some new features: BIG_LEAP_PROMO, ATTACH_SINGLE_PHOTO, TWO_PANE_UI (for iPad).
{ Thanks, Florian K. }