Most of the video editing tools are desktop apps, sometime you need to edit video but you are in outside. Loopster is an online video editing tool. For using this service you must sign up in loopster. You can also sign up via your existing facebook account.
After the sign up you can edit your videos here you can add text, trim and add sound track. It cannot give professional editing. After edit your video you can publish it. You can download your videos as MPEG format.
If you want to draw or type text on webpage and take screenshot, Screen draw is a Firefox add-on that will help you to draw and type text on webpage .After your draw or type you can save that image in png or jpeg format.
This adds on help you to annotation mark or add text on webpage. You can simply add this add-on your browser after the installation you can seen Draw icon bottom part of the webpage click on that icon you can start your painting.
Download this add-on add click here