As with a desktop computer, you can't do much beyond the basics—granted, that's a lot sometimes—with most PDAs and smartphones without third-party software. Hence, the development of a lucrative third-party mobile software market over the years.

Although there are a number of ways to purchase mobile software, one of the most popular sources is Handango. The handheld application retailer has released the April 2005 edition of its Yardstick, a report on what people are downloading and purchasing for their smartphones, mobile phones and PDAs.

Here’s what the Yardstick says:

Surprisingly, for the first time since the fourth quarter of 2003, Hewlett-Packard’s iPAQ h5000 series was the number one device adding software, while the long-time reigning champion, the Tungsten T Series, dropped to number three.

The BlackBerry 7250, ranking number three on the list of top phones adding software based on revenue, is the first BlackBerry device to make the top five since the Handango Yardstick launched during the second quarter of 2002. Expect to see more BlackBerry handhelds on the list over the next few months due to Research In Motion’s (RIM) impressive recent success.

Another first-time appearance was made by the palmOne Zire 71/72, which ranked number five for handhelds adding software by revenue.

Ten best-selling applications by operating system:

Palm PDA/Smartphones
1. AOL
2. Agendus Professional Edition
3. Ringo Pro
4. Agendus for Windows Outlook
5. PocketMirror Standard
6. Village Sim
7. Treo Voice Dialing
8. KeySuite
9. Diet & Exercise Assistant
10. SplashID

Windows Mobile Smartphone
1. SmartphoneNotes
2. Papyrus
3. ClearVue Suite
4. Battery Pack Pro
5. PocketMusic Player
6. WorldMate
7. Pocket Streets
8. CodeWallet Pro
9. eWallet
10. Jeyo Mobile Extender

Windows Mobile Pocket PC/ Pocket PC Phones
1. Pocket Informant
2. Spb Pocket Plus
3. Pocket-DVD Studio
4. Agenda Fusion 7
5. Microsoft Voice Command
6. ClearVue Suite
7. Spb Diary
8. Battery Pack Pro
9. eWallet
10. Pocket Controller-Professional

Symbian Smartphones
1. Handy Day
2. SmartMovie
3. WebViewer
4. Remote
5. Quickoffice Premier
6. SKY FORCE
7. Handy Safe
8. WorldMate Professional Edition
9. Handy Tools
10. Quickoffice Premier

RIM BlackBerry
1. WebViewer
2. Ring Tone Megaplex
3. MP3 Ringtones
4. Aces Texas Hold'em - No Limit
5. WorldMate Standard Edition
6. Reqwireless Value Bundle
7. WorldMate Professional Edition
8. Sol Mania
9. IM+
10. Card Games: Pack One