How do you do downloads? Do you wait for payment to clear in paypal and send them a link, or provide a download right away? Or is the download the usual free app and payment gets them the key?
I do free trial automatically becomes full version with presence of key. In most markets, I would send out keys IMMEDIATELY on payment -- the risk of fraud is insubstantial (most people won't try to cheat you and the ones that will, oh well, all you lose is a few server cycles generating a new key) but the immediacy of instant delivery helps lift conversion rates substantially.
(I got +5% sales when I stopped calling my purchase option "Purchase a single copy via download" and instead said "Get it instantly via download". Love that word "instant".)
Some of my friends, who are more worried about fraud than I am, do instant delivery of temporary keys and then provide the permanent key after a few days. I resist doing this largely because it causes a hassle to my customers without gaining them any extra benefits. (Plus, key management is already a major source of tech support headaches, why double the load?)
Props on content-limited trial. Time-based trials suck. With time trials, half the time I download it, use it for a day, then want to try it again 3 months later but can't.
Panic have a slight twist on this; Coda comes with a 14 day trial, but that's 14 days of use. This means if you use it for 4 days then don't touch it for a month, you still have 10 days remaining.
* More updates = more traffic = more sales, because each update gets you near the top of the download sites
If this is true for the iPhone AppStore as well, this would explain the endless annoyance of millions of Apps doing fourth-digit updates two times a week. I actually find myself prompted with updating some applications more often than I use them.
Automatic updates are cool, but with all software everywhere interrupting your flow, begging about updates, it's getting quite annoying.
* For distribution, I just have a website. I also put it up on the Apple downloads listing, which is where most of my traffic comes from.
* A bunch of other sites pull data from Apple's listings, so I get traffic from there too.
* More updates = more traffic = more sales, because each update gets you near the top of the download sites
* Sales are done through PayPal, which is really easy to setup
* Support email isn't bad at all, maybe 1 email every other day
* The free trial limits the amount of data you can enter, rather than a time trial. That way users can try out future updates too.
* When a major site did a post about it, sales AND feature request emails spiked. But after a week, it goes back to normal.