Hardy Macia, known for PocketMoney and MPG, sent an email today with a warning many of us might be overlooking. Some apps, not yet tuned for iOS4, may not work as they do now on your 3.x OS iPhone.

A lot of developers have updated their apps to run on iOS4, enhancing to use new capabilities brought about by the OS for new features. When a OS is released, not all things remain the same in the background that a developer might be using which means some features will not function. If there is an app that you really depend on everyday, you may want to double check to make sure it has either been updated or at leasted tested on the new OS before you update.

From Hardy’s email today:

PocketMoney for iOS warning:
If you are a PocketMoney for iPhone/iPod Touch user, then please do not upgrade to iOS 4.0 immediately, but wait for PocketMoney 3.0.6 to be approved by Apple before upgrading to iOS 4.0.

There is a serious bug that prevents the custom amount keyboard from displaying with the decimal point button. So if you upgrade to iOS 4.0 you will not be able to enter decimal points — the work around is to copy and paste a decimal point into the amount field.

PocketMoney iPad/iPhone Syncing and PocketMoney for Windows/OS X
The upcoming version 3.1 of PocketMoney will have iOS device to iOS device syncing. It will also be able to sync to the desktop version of PocketMoney that is currently in development. I had pushed for a June 16th release for my birthday, but there were still a couple bugs and some polishing that needs to be done before I feel comfortable releasing it to all of you. I will send another email out when 3.1/Desktop is officially available. I’m really excited for it.

MPG for iOS 4.0 warning:
The same warning applies to MPG users with the decimal point. Version 1.3 has been submitted to Apple and is awaiting approval. It also adds support for the iPad screen size.

A new app just for iOS 4.0. I’ll be submitting it this week to Apple for review. There are three things that I wished the built in calendar did. 1) Display a badge for the number of appointment I have left today — Messages, Mail, and Phone all show you what you are missing — Today! gives you a quick look at your appointments. 2) Clicking on the location will open Maps to route you to your next appointment. 3) Set the default alarm time for new events you create through Today!, and 4) Lists your appointments so you can see the location and notes.