If you don't have an iPhone or BlackBerry you can still do it. Well I don't know how to do pictures but I can tell you how to do updates.
Click on "My Account", then "Mobile". From here you will click on the selection to add a phone number. It will tell you to send a text to a certain number, then text you back a confirmation number. You have to enter that confirmation number on the Mobile screen. After that you make your selections for the settings. You can set it to notify you of comments on your page from 8 am - 9 pm if you want or any other time that works for you.
Let me know if you have any other questions or have any problems.