How to scroll up and down a mobile document

Question

Assume you are using a mobile device where the only scrolling method is an up/down control - no scrollbars or other 'proportional' controls. You are viewing documents which typically have many links or other fields that can accept input, but may also have significant lengths of text without such fields. What is the preferred way of scrolling:

1. a scroll move goes to the next link, unless it's more than a screen height away, in which case it moves some fraction of a screen height;
2. a scroll moves a cursor which scrolls as necessary to keep the cursor on screen; this gives smooth scrolling but makes it more difficult to select a link;
3. Some other approach I haven't thought of

Answer 1

Browsing and reading is more likely to be the more common operation than clicking on links. I never liked #1 because of that.

Modern mobile browsers (e.g. Opera Mini 4 and Nokia's browser on smartphones) often uses a "mouse" cursor, as described in #2. It's still a bit clunky, but definitely much better than #1.

I liked touch screen scrolling, it's definitely the best for scrolling through large amount of text (flick and fling is important, it allows you to "throw" the page to scroll through very large amounts of text). However, touchscreen is also the worst when it comes to clicking links.

Something that I haven't seen attempted, is modal browsing. There are two modes: browsing mode and clicking mode. In browsing mode, the up and down buttons acts like #2, ignoring any links present and just for scrolling the page. In clicking mode, the up and down buttons acts like #1, going through every links for selection. Modal browsing is probably going to be a little bit daunting for new users, but it may be convenient once you're used to it. If you have the luxury of four vertical buttons (e.g. a pair from directional button and another pair from number pad 2 and 8), then you may not even need to make it modal.

Answer 2

Based on your list of assumptions, #1 is not an option in any way - there's no way to view the full content of the page that way.

#2 makes more sense to me. Of course, with that method, you would need to at least have a touch interface to select the fields to allow entry of data.

Another method that could be done is a combination of both #1 and #2. It scrolls smoothly until you come to a spot where it has a field for data entry. The next scroll button press takes you into the field, and then the subsequent scroll button press takes you out and lets you scroll further normally. I'm pretty sure this is actually what mobile devices like the Blackberry do (although my experience with Blackberry is pretty much watching other people use it).

Answer 3

If your mobile device has accelerometers, I've seen a neat idea in some iPhone/iPod touch apps: tilt the device slightly forward or backward, and watch the page scroll. Tilt more to scroll faster.

Answer 4

Opera Mini also uses the phone's number pad as a scroll mechanism. The normal up/down control scrolls the page smoothly, like #2. But if you press 2/8, the page scrolls one page at a time. The negative side is that you have to let users know they can use the number pad for navigation, because it is not completely natural or intuitive to phone users. I myself discovered it by accident. The positive side: the sooner your users learn that they can use the number pad, the easier it will be for you to add other functions to the program in a directly accessible way.