Ads only on free apps is a good policy--I just wish authors would stick to that model. Unfortunately, the more popular a paid app becomes, the more temptation there is to milk the cash cow with a few ads.
I've found that Apps I've paid for tend not to have ads. I don't mind ads on my free apps, I realize the author should be able to earn an income from their work. It's a choice of marketing. Free but ad-paid vs. a paid download.
Yes, this trend has got to be scary for any company will all their eggs in the PC basket. Microsoft is responding with mobile OS offerings and Intel with mobile Atom processors, but it will be hard to put the genie back in the bottle.
I believe this may be what some call an "inflection point". Technology and human use of that technology is moving away from the current status quo.
For example, from what I have heard (and need to confirm), outside of the US most people access the web through some sort of mobile device. Imagine what that says about companies supporting that infrastructure--suddenly ARM and Linux, instead of MS and Intel are central.
Those apps are not just replicas of desktop applications, but whole new applications impossible or of little use on LAN based computers. Brand new world--suddenly its not compilers, spreadsheets, word processors or Windows anymore.
Yes, even the iPad has a few ads already, for instance "Prudential" has a banner that displays during the startup of the MLB app. But these are just the tip of the iceburg. Apple's iAd and Google's mobile AdSense aim to put as many flashing "invitations to buy" in apps as there are on web pages. Lets just hope they don't spoil the burgeoning App Culture by being as intrusive as those auto-playing flash-videos are on the web.
Apps can be more secure than browsers, because well written ones will use proprietary security algorithms that can only be cracked by targeting them specifically--not by getting in through a web browser's security holes. Hackers seem to be attracted to challenges, however, which is why app developers need to take care with their implementations. For instance, Citibank recently confessed that it had to plug a security hole in one of its apps:
The bigger worry is from hackers writing their own apps with hidden Trojan horses inside that they then give away free!
"Apps move e-commerce off the Web and onto a more secure mobile Internet platform". This statement about the security of using apps for ecommerce could be misleading.
I suppose hackers should still be able to commandeer apps running on our mobile phones and steal user information.