WARNING: Do NOT convert your HP Prime programs into applications!

[Kevin Ouellet]

I am posting this because I notice that more and more HP programmers are switching from program to apps lately, and they might be doing so too early. If you are working on HP Prime programs and another member or even an HP staff suggests that you convert your program into an application, I highly advise you against doing so. Do NOT convert your HP Prime programs into applications! Otherwise, you will simply make it next to impossible for everyone else to use your softwares and reduce your audience in the process.

Two OSes ago, HP implemented support for custom icons and including images inside your applications, with the ability to send the folder containing the files into your applications library via the HP Connectivity Kit software. However, despite claims that it is supposed to make it easier to launch and distribute softwares (they show up in the application list), it is currently the complete opposite. Not only support for this new application format (.hpappdir) is completely broken in both firmwares that support it, but there is no official documentation on how to send such application to your calculator and once you know how to do it, there are about 90% chances that the game or software will not run at all: Instead, a spreadsheet or graph will show up, and that, even if this advice by Timwessman is followed. There are also chances that the calculator will freeze during application transfer, as I witnessed twice, requiring a paper clip to press the RESET button on the back of the device (since ON+Symb won't help you there).

Also, there is only one specific way to transfer an application to the calculator: Sending the ZIP file itself will not send the custom icon and going inside the folder then sending all files at once from there will not send them at all, so your solution is to send the folder, unzipped. And then, that's if it sends at all and if it does, then it's not guaranteed that the result will work as intended.

Until HP fixes all of this, we highly recommend everyone to stick to the .hpprgm format. This will allow you to keep your games and softwares into 1 file and if more than 1 file is required, then at least there won't be all the serious transfer issues that comes with .hpappdir transfers. In addition to that, it's easier to debug code on-calc.

HP, If it ain't broke, don't fix it. Or at least, don't replace it with something even more broken than the HP 39gII.

Cross-posted from http://codewalr.us/index.php?topic=610.0 (also at http://tiplanet.org/forum/viewtopic.php?f=69&t=16955 in French)