If you use presentation apps to customize existing stock presentations for specific audiences by rearranging slides and changing text, then Web-based apps may serve your needs nicely. But if you're the Cecil B. DeMille of PowerPoint -- if your presentations are loaded with reveals and fly-in objects and transitions -- you may find that even ThinkFree, the most full-featured of the lot, is barely adequate.
The presentation apps in the Web-based suites are more limited than the word-processing and spreadsheet applications. ThinkFree Show sticks closely to PowerPoint, but Google Docs and Zoho Show are both missing standard, often-used features like layout grids and slide transitions -- and even, in the case of Google Docs, clip art.
Even ThinkFree has its limitations. It won't do everything PowerPoint does. Among other things, its selections of presentation designs and clip art are limited, and there's no "insert movie" feature.
Another limitation is size -- all three Web-based suites limit the size of presentations you can upload from your computer to 10MB. That's obviously a number chosen to hold down file transfer times, because presentations -- especially if they include video or many photographs -- can be much larger.
Fortunately, once your presentation is uploaded, it can grow to whatever the limits of your storage space are. If you customize your presentations by combining slides from several sources, then you'll want to use Google Docs or ThinkFree: They let you cut and paste slides between presentations; Zoho doesn't.
However, Zoho compensates for some of its shortcomings by offering the widest variety of presentation design templates (about 50), and the most useful clip art and symbol collections. ThinkFree includes 33 presentation designs, and Google Docs only has 15.
Google Docs, for its part, does one trick the others don't -- you can embed a YouTube video in a slide. Given that just about any video is, or can be, available on YouTube, that can be very useful. (You don't suppose it has anything to do with the fact that Google owns YouTube, do you?)
Google Docs has another feature, in some ways more impressive, that it shares with Zoho Show: you can invite others via e-mail to watch the presentation while you control it. It's an easy way to support a conference call with visuals -- put up the agenda and other information as a quick presentation, and send an invitation to the attendees as a group. When they click on a link, they'll join a real-time presentation that you can control.
Zoho improves on this, although the process is more complicated: You can view the speaker notes while hiding them from your audience. And thanks to the range of Zoho's online applications, you can switch to Zoho Meeting from within the presentation and share your desktop with the attendees. (Unsharing the desktop and getting back into controlling the presentation, though, can be a challenge.)
Picking a Winner:
Zoho Show's wide variety of templates and clip art makes it the most useful of the three apps, and its integration with Zoho Meeting gives you a new presentation tool you haven't had before.