Building your own portable working environment on a USB flash drive is undoubtedly convenient. Equip it with your favourite productivity software, browser, email client, graphics tools and games and it’ll always be ready for use on any nearby PC.

One issue you’ll notice straight away, though, is performance. The USB interface may be fast, but flash drive read and write speeds really aren’t, and even small applications can take quite a while to launch.

You can of course try to buy extra performance by shopping specifically for USB drives with the fastest possible read/ write speeds. But a free alternative may be to compress your application executable files with AppCompactor. You can cut their size by up to 50%, which could make a real difference to launch time. And although the program must automatically decompress itself whenever it’s launched, this is a relatively fast process so you could still see major performance benefits.

Compress your portable applications with a click

While this sounds like it’s going to be a very technical process, AppCompactor is actually surprisingly easy to use: just point the program at your portable app’s folder, choose a compression method and click “Go”. A moment later you’ll get a report on the space saved, if any, and can test the application yourself to see if you notice any difference.

One difference you may notice is that your portable app doesn’t work any more; AppCompactor is as reliable as this kind of tool gets (which is why PortableApps.com use it with big-name portable products like OpenOffice.org and GIMP), but there are no guarantees, and it won’t work with everything. So it’s a very good idea to back up your portable application before you start.

And as malware authors routinely use similar packers to try and hide from security packages, doing so yourself increases the chance that your compressed portable app will raise a virus alert when you next launch it. This isn’t particularly likely – AppCompactor is a well-known package and not doing anything dubious – but can’t be ruled out entirely.

For the most part, though, AppCompactor just delivers exactly what it promises, quickly compressing executable files – DLLs, EXEs, ZIPs, JARs, IRCs, PYDs and BINs – with the minimum of hassle. So if you’d like to accelerate the launch time of your portable apps, then give it a try: it’s surprising just how effective the program can be.