What I dislike about using the mobile flickr site through the browser is
1) the images are too small. I want full-sized image that I can swipe through like the Android gallery.
2) when I click on the small image to view a larger version I can't scroll right, so I can only see the left site of images that are wider than my screen.
3) navigation isn't intuitive. To get a specific set of images, after logging in I have to go to "You", which brings up my entire photostream, then click the "..." in the upper-right, then "Sets", then select the set I want to see. Between each click I have to wait for the next page to load. Too cumbersome.
JustPictures is free and I can pinch & zoom and move around the image. Plus, JustPictures catches my images, so swiping though a set is super quick; no waiting for the image to download each time. You could have JP automatically sync with flickr. I only sync after I've uploaded to flickr. I just long-press on the flickr gallery within the app and select pre-fetch images. I'm usually at home on wi-fi when I do this, so it's faster. This way I'm not wasting battery power using 3G on the mobile site when I'm on the go.