hallo, it is sometimes not very beautiful to add title and caption for all rollover (especially if you use rollover also for nav bar)  so, if people really like to see the comment or the name of the file to order, like mobile look, they rollover and click on info icon on top right.

the galery icon in nav bar works nice but the look especially in full screen is not beautiful. a nav bar of albums at top like mobile is so cute ! in your examples you also have a special effect with thumbgrid with two rows of thumbs and when you click on external button (why doing external buttons for examples nobody can use !) a row of big album thumbs appear. but let's focus first on mobile look with top rollover album icon : really nice but it is my opinion !

the idea i have for years but not skill enough in thumbgrid is to have one nav bar with only images. no buttons except two cute arrows on side for prev and next. all the other functions would be rollover or on a control bar appearing on rollover like simpleviewer.
when i saw your mobile look i thought "this is what i wanted"...

best regards