It's not often I test an app that leaves me inspired about its possibilities. That's been the case with Electric Slide. This free app (restrictions described below) lets you give a presentation using PowerPoint, a document or a PDF to up to five people wherever they are in the world. You can originate your presentation from any computer, or almost any iOS device (specific iOS requirements at the end of this post).
Once you upload your files to the Electric Slide servers, participants log in from a browser (or iPhone or iPad app) and watch in real time. For audio, you'll have to rely on a conference call or third-party audio conference software.
To test the service, I uploaded a Keynote presentation I converted to PowerPoint, plus a PDF file. The upload was fast, and within seconds the presentation was available on the web. I shared it with a few friends, changing pages on my iPad, and confirmed that page changes were virtually instantaneous. Color fidelity was accurate. Others viewed my presentation in Safari on OS X with no issues. I could also access a presentation using the Electric Slide iPhone app. Although the slides were a bit small, they were perfectly readable with the phone in landscape mode.
People who do presentations frequently will be excited about the Electric Slide service. Your audience can join from the airport or a car from any iOS device or laptop.
Now about the limitations and costs. You can use the app for free, but presentations are limited to 90 minutes with no more than five participants. You can upload a total of 50 MB for free to the Electric Slide servers. Many people will want or need more, so that's when the costs come in.
For US$26.99, you get three months of service, which includes 1 GB of storage, up to 50 viewers, and no length restrictions on meetings. A six-month plan is $48.99, and an annual plan will set you back $79.99. Given the quality of the service, and ease of use, this pricing is not too high.