[Windows Mobile Development and Hacking General] Menneisyys:
2. Available MIDlet managers

In this chapter, I give you a thorough overview of what current (!) MIDlet environments there are, how they compare to each other and which one you should prefer. As you’ll see, particularly if you’re a power user and/or player, you will want to keep different KVM’s on your Windows Mobile handheld simultaneously so that you can make use of the functionality of each of them (there’s no “best” KVM – unfortunately, the otherwise best Jbed lacks some functionality only provided by other KVM’s).

Note that I don’t provide you download /purchase links here. You can find all of the download sources and / or accessibility remarks in the main chart, in the second, “Price / availability” row.

Also note that this is just a sketchy list of what KVM’s there are and what (dis)advantages they have. For a full list of tips, tricks, capability and problem lists, you MUST consult the above-mentioned main chart. Note that, in Chapter 4, I will also elaborate on the meaning of the rows in the chart.

2.1 Esmertec Jbed

This is by far the best and most recommended KVM for Windows Mobile, (QVGA; NOT 176*220 – on the latter, it refuses running deployed MIDlets) Smartphones and Pocket PC’s alike. Its only problems are the lack of M3G (3D gaming) support and the inability to run more than one MIDlet concurrently. As with the other products of Esmertec, it isn’t compatible with pre-WM5 operating systems and needs to be “hacked” in order to be able to run it on non-Phone Edition Pocket PC devices. (See the “Platform compatibility: non-phone PPC” row in the main chart to see how this hacking must be done.)

Note that the latest, currently available Jbed version has problems with the cookie handling of Opera Mini 4 beta 2. This means you can’t log in to many (but not all; for example, Yahoo Mail works) Web sites with OM4b2 running under Jbed. As this isn’t an issue with Opera Mini Mod 2.04/2.05, this seems to be a problem exclusively with the given Opera Mini version and not that of Jbed. If this is a problem, consider switching to another MIDlet manager (for example, Jeodek), where the cookies of Opera Mini 4 beta 2 do work.

2.2 Esmertec Jeodek

There are, basically, two versions of this KVM. The non-M3G-enabled, newer version isn’t really recommended (Jbed is definitely better in almost every respect, except for the Opera Mini 4 beta 2 cookie issues). There is, however, an older, M3G-enabled version out there, which allows for playing a wide variety of games. I’ve explained how the latter should be used HERE, in the 10/11/2007 update. That is, if you’re into gaming, you might want to go for the M3G version; otherwise, I recommend upgrading / switching to Jbed.

2.3 IBM J9

This is a well-known but, now that both Jblend and the two product lines of Esmertec are considerably better in most respects (except for some deliberate questions like the ability to run multiple MIDlets at the same time, in which it’s, together with TAO Intent, is clearly better than Esmertec’s products), not any more recommended KVM. You should prefer Jbed to it and only consider using it if you do need J9’s special capabilities or its compatibility with pre-WM5 operating systems.

Note that, lately, IBM has made much harder to download a trial version of J9 if you’re situated outside the States.

2.4 TAO Intent

This is the MIDlet manager having come with almost all HTC-manufactured WM5 Pocket PC’s and Smartphones. Now that the developer no longer exists, the HTC folks have switched to Esmertec Jeodek / Jbed instead (and independent MS Smartphone / PPC PE manufacturers like Sharp or Samsung prefer Aplix JBlend instead). However, this still means there’s a HUGE number of installed userbase of this MIDlet manager.

Currently, two major releases of these titles are widely used: the 10.1 series (also compatible with WM2003(SE) and the MS Smartphone platform) and the latest 11.1 series (the latter being only WM5+ & Pocket PC-compliant).

In general, you will want to prefer Jbed to this title. It has only few areas where it’s clearly better. Just like with IBM J9, in addition to WM2003(SE) support, it also supports running MIDlets concurrently.

If you have a (non-rebranded!) HTC WM6 Pocket PC device, go for the latest, .1036 version; otherwise (you have a rebranded and/or WM5 device), go for .1034. Should you have a plain (non-phone) Pocket PC, make sure you apply the SMS.dll / Phone.dll hacks already mentioned with Jbed.

Note that, at 4pda.ru, there is a separate “turbo” version. While I haven’t really measured remarkable speed increase with the jBenchmark tests, many users have reported generic speedup with at least starting / loading MIDlets. This is because many library files have been decompressed by the creator, meaning no decompression needed in runtime. This may indeed result in some speed increase. (Note that this trick doesn’t work the 10.1-series TAO Intent MIDlet managers (MM’s); this is why only the new series has a separate “turbo” version.) Note that this also means this version occupies about two times more storage than the non-turbo one; therefore, if you have little built-in storage, consider installing it on a storage card. Also, it’s a bit older (version 1023) than the – currently – latest, 1036 version.

2.5 Aplix JBlend

This OEM MIDlet manager comes with, compared to Esmertec’s KVM’s, very few Windows Mobile models. Compared to Jbed, it has both advantages and disadvantages; for example, it supports M3G (and, therefore, far more games) BUT it doesn’t support midi / MP3 playback (that is, you won’t really hear music anywhere) and has a messed-up security model making it pretty useless for Net access like Opera Mini or Gmail. This means you will only want to use it for gaming – if the other two, decent alternatives (the M3G-enabled Jeodek or Jbed) don’t work or work slower.

In THIS HowardForums thread, you’ll find many titles compatible with this MIDlet manager; and, of course, my main games compatibility chart will provide you with a lot of additional compatibility information with current MIDlets.

2.6. Not recommended KVM’s

Note that the charts (and this tutorial) don't elaborate on the following MIDlet managers:

2.6.1 NSICom CrE-ME

This manager is still (as of version 4.12) pretty weak (MIDP 1-only, really low resolution, problems with connecting to the Net, pretty complicated to install a MIDlet etc.). This means it, in most cases, should not be used. Strange the developers still call it "the world's most reliable J2ME/CDC Java Virtual Machine technology for Embedded platforms". While CrE-ME is without doubt the BEST JVM out there right now for running individual applications / applets (which are vastly different from MIDlets), its MIDlet support is really bad.

2.6.2 Coretek Delta Java Manager

This MIDlet manager is only slightly better than NSICom's above-mentioned CrE-ME. While it's compatible with quite a few games, it has severe problems; most importantly, its utilized screen estate is tied to 176*220 (fortunately, it’s pixel doubled on VGA devices). This means you won't be able to run your MIDlets using the real, full screen estate of your QVGA / VGA / WVGA Pocket PC's or QVGA Smartphones. Therefore, I only recommend it if you want to run MIDlets tied to 176*220 (or smaller) screen sizes and/or you have a 176*220 MS Smartphone.

A related (Russian) thread is HERE (BabelFish HERE)

2.6.3 Mitac JVM

This is an old (2003), pretty bad and not recommended MIDlet manager.

Related thread: MoDaCo Working midlets and non-working midlets.