PDA, Notebook and Phone Reviews and buyers guide

PDA Phone Notebooks Gaming Gadgets iPhone & iPad Shop Discussion


PDA Reviews

HP iPAQ 4155 Pocket PC

Reviewed by Lisa Gade, Editor in Chief, Nov. 25th, 2003

The 4155 is being phased out with the release of the Fall 2004 iPAQ rx3115 and rx3715

HP has been hitting home runs this year with their latest iPAQ Pocket PCs. The iPAQ 5555, 1945 and particularly the 2215 have been great models that have been well received by reviewers and shoppers alike. The 4150, much anticipated since rumors of it surfaced several months ago, should also be a hot unit. Why? It's just a hair larger than the iPAQ 1945 which is the smallest Pocket PC, yet it offers both built-in Bluetooth and WiFi and has no external antennas. In short, it's absolutely sweet! Note that in the HP tradition, the iPAQ 4150 and 4155 are the same unit, the final digit indicates whether it was sold via consumer or business channels. We have the 4155, so will use that model number in our review. Note that the iPAQ 4350 is a 4150 with an integrated thumb keyboard and larger battery, and that unit is 1 inch longer to accomodate the thumboard.

iPAQ 4155
iPAQ 4155 back


Design and Ergonomics

It's surprisingly small, it's curvy, modern, attractive and light at 4.67 ounces. Think Palm V sized, or the iPAQ 1910 and 1940, if you've seen those in person. Unlike most other Pocket PCs with integrated WiFi, the 4155 doesn't have an external antenna, making for a cleaner and more compact design. Don't worry, WiFi signal strength is top notch even without the antenna.

The casing is made of plastic, and the front face has a silver finish. The back of the case is gray plastic, and while it doesn't give the iPAQ a touch of class, it should at least not show fingerprints. The user replaceable battery lives behind a door on the back and you'll slide a chromed retaining latch to release the door.

On the front are 2 LEDs, one of which glows green to indicate that the WiFi radio is on, and blue to indicate that the Bluetooth radio is on. If both Bluetooth and WiFi are turned on, the LED will alternate between blue and green. The other LED indicates charging status and reminders in amber. The record button is located on the upper left side and is well designed to avoid accidental button presses. The 5-way square d-pad works well and smoothly in all directions, but the four application buttons are small and a bit slippery thanks to their chrome finish and will likely not thrill gamers. Oddly, the IR port is located on the bottom right corner which means you'll be looking at the screen upside down when beaming, and most IR keyboards won't work.

HP designed a new cradle for the iPAQ 4000 series and it's pictured on the right below. It's a relatively large and blocky looking cradle, and the iPAQ stands upright leaving a good deal of space behind it. Why the space? To make it easier to get to spare batteries that are being charged in the rear section of the cradle even when your iPAQ is cradled. This is the first HP cradle to feature a removable standard USB cable.

iPAQ 4000 series cradle

Above: the iPAQ 4000 series cradle. The inset on the back plane is for charging a spare battery.

size comparison

Above: Size comparison. Left to right: Dell Axim X3i, iPAQ 4155 and the Sony Clié UX50.



Deals and Shopping!



Questions? Comments?
Post them in our Discussion Forum!


Horsepower and Features

The 4155 has an Intel XScale PXA255 processor running at 400 MHz. This is the current top of the line processor, also used in the iPAQ 2215 and 5555, and the 4155 benchmarks similarly to those units. The 4155 has 64 megs of RAM, 55 of which are accessible to the user, and 32 megs of NAND flash ROM, 2.85 megs of which are available as a non-volatile File Store. HP has shipped the 4155 with a utility that can format the File Store area should it become corrupt or should you wish to erase its contents before selling it or giving it to someone (being non-volatile, the File Store will not be erased even after a hard reset).

The iPAQ runs Pocket PC 2003 Premium Edition, which is the full featured version of the OS (compared to PPC 2003 Professional Edition). This means MS Reader, Terminal Services and Microsoft's new Images program come pre-installed in ROM.

For expansion, you've got the oddly placed IR port, Bluetooth and an SD slot supporting SDIO. The 4000 series iPAQs are not compatible with iPAQ expansion sleeves for the iPAQ 3000 and 5000 series.

Video playback was excellent using Pocket MVP and Pocket TV Enterprise. In fact, the 4155 outperformed our Dell Axim X3i, dropping many fewer frames for videos encoded at high rates.

Screen, Sound, and Gaming

Transflective displays, currently one of the best LCD display technologies have become standard on Pocket PCs, if not most all recent PDAs, and the 4155 has a 3.5" transflective display. HP makes some of the nicest, and they're always bright, color saturated and contrasty. The 4155 is no exception, having a lovely display, but if you hold the unit at an angle rather than holding it straight on, you will notice a yellow color cast. When held straight on, you won't see it at all, and it isn't as noticeable as the iPAQ 1945's off angle color cast.

The sound volume is quite loud. Alarms are easy to hear, and I generally turned down the sound level to less than half when playing games. Of course if you're listening to MP3s, you'll want to use headphones that connect to the standard 3.5mm stereo headphone jack rather than the speaker located under the d-pad. Like all Pocket PCs, the iPAQ 4150 has a voice recorder, and the unit includes an Audio control panel applet that allows you to adjust the microphone EQ for "Short Range Recording", "Normal" and "Conference Recording". You can also enable AGC (automatic gain control), and set the headphone volume independent of the speaker volume.

The 4155 performed well playing intensive games including NES emulators, Hexacto Bounty Hunter Pinball, SIMCity 2000 and Bust 'Em 2. Other than the application buttons, gamers should enjoy this unit.

Battery Life

The 4155 comes with a user replaceable 1000 MAh Lithium Ion battery. That's a decent capacity battery, and an optional extended 1800 MAh battery is available. The newly designed cradle has a slot to charge an additional battery. Like other iPAQs, you'll use the included dongle if you wish to plug the charger directly into the iPAQ rather than charging it in the cradle

Battery life has been impressive so far, averaging 3.5 hours when not using wireless (brightness set one notch below highest). Even intensive games don't rapidly drain the battery. Bluetooth is always fairly battery friendly, but WiFi is not. Despite that, the iPAQ achieved about 2 hours when using WiFi. I used the iPAQ with the WiFi radio set to auto power savings, and there are also options to always use power savings ("Extended") or never use it ("Off"). These settings are found in the Power control panel applet, under the "Control" tab.


The iPAQ 4155 has built-in WiFi 802.11b wireless Ethernet networking. It truly has excellent range considering that it doesn't have an external antenna. In fact it rivaled the iPAQ 5555 which also has excellent range. Using Cirond's Pocket WiNc, I was able to sniff out 11 WiFi access points in my home area (it's Silicon Valley, after all). The wireless control application looks like the one on past iPAQs: it allows you to turn on and off either or both radios, and there are no external switches to activate the radios. Windows Mobile 2003 comes with a certificates application, and in addition, HP supports LEAP on their WiFi enabled Pocket PCs. The 4155 has a LEAP control panel applet and HP's Enroll, a certificate enroller.


The iPAQ 4155 uses HP's Bluetooth Wizard which is powerful and user-friendly. It walks you through connecting to a variety of devices, from your ActiveSync partner (if you have a USB Bluetooth adapter installed on your PC), to mobile phones to access points and GPS units (it doesn't support Bluetooth headsets). The Bluetooth software is made by Widcomm and is version 1.4.1. I ActiveSync-ed wirelessly, connected to Belkin and Red-M Bluetooth access points for Internet access and, transferred files to other Bluetooth enabled Pocket PCs. Speeds when ActiveSyncing and surfing the Net were good, though not as fast as using WiFi, which is to be expected since WiFi offers greater speeds.

screen shot


While the 4000 series iPAQs are not compatible with iPAQ expansion sleeves, the connector on the bottom of the unit is the same as that used on the iPAQ 2215, 3000 and 5000 series iPAQs, so you should be able to use those accessories that connect to this port with the 4150 (yay!). This means iPAQ keyboards, GPS and chargers made for those models will work.

Software Bundle

HP always offers a good software bundle with their iPAQ Pocket PCs. The 4150 came with the usual suite of iPAQ custom applications: iTask task manager, iPAQ Backup (SpriteSoft), HP Mobile Printing, HP Certificate Enroller, LEAP, Bluetooth Manager and their iPAQ Image Zone (HP's improved image viewer). Note that unit doesn't come with Nevo, the ever-popular AV remote software, which is installed in ROM on the iPAQ 2215 and on the now discontinued iPAQ 3900 series and iPAQ 5450. Pocket PC standard apps include Pocket versions of Word, Excel and Outlook, MSN Messenger, Terminal Services, VPN client, Jawbreaker (a Bubblets game) and ClearType Tuner. 3rd party apps include Westtek ClearVue Suite (for viewing MS Office docs), Resco File Explorer 2003, F-Secure FileCrypto Data Encryption, RealOne Player for Pocket PC and iPresenter PowerPoint converter.


We've run benchmarks using VOBenchmark 3 from Virtual Office Systems. I've compared the iPAQ 2215, iPAQ 5555 , and the iPAQ 1945 to the 4155. All tests were run with units fresh out of the box with no other software added, and the storage cards were 60% full with data and applications. For some reason, our 4155 didn't get along with the storage card write tests, so we weren't able to record values for the storage cards tests. Higher numbers are better (shown in bold).

Test HP iPAQ 2215 (PPC 2003, Intel PXA 255 400 MHz processor) iPAQ 5555 (PPC 2003, XScale PXA255 400 MHz) HP iPAQ 1945 (Samsung 266 MHz) iPAQ 4155 (PPC 2003, XScale PXA255 400 MHz)
CPU Floating Point 12.68 12.66 9.33 12.69
CPU Integer 26.96 25.82 18.39 26.96
Graphics Bitmap BitBlt 78.25 39.76 28.06 22.39
Graphics Bitmap StretchBlt 76.70 (grow) 28.60 (shrink) 73.50 (grow), 29.90 (shrink) 14.40 (grow) 11.50 (shrink) 18.70 (grow), 15.70 (shrink)
Graphics Filled Ellipse 4.68 4.96 2.67 4.79
Graphics Filled Rectangle 12.94 9.41 5.99 11.15
Graphics Filled Round Rect. 3.82 3.78 2.15 3.76
GAPI Lines N/A N/A 35.90 58.90
Memory Allocation 11.23 11.31 8.56 11.27
Memory Fill 1.97 1.99 1.34 1.91
Memory Move 1.24 1.34 0.77 1.22
Text 5.20 with ClearType enabled 4.80 with ClearType Enabled 6.20 with ClearType enabled 9.10 with ClearType Enabled


If you're looking for a power handheld in a small package, then the iPAQ 4155 may be the ticket. It's as small as the iPAQ 1900 series (OK, hair larger), yet has a top of the line processor, Bluetooth, WiFi and supports SDIO. Add in compatibility with iPAQ connector accessories such as keyboards and GPS and you're set. This model should be great for folks who coveted the iPAQ 5555's strong networking features and processor, but wanted something smaller and less expensive.

Pro: Fast processor, excellent display, integrated Bluetooth and WiFi that has very good range. Extremely small, light and attractive. User replaceable battery. Cons: More expensive than lower end Pocket PCs on the market, but you do get a lot for your money, and an amazing hardware suite fitted into a very small unit. Application buttons aren't a gamer's dream. No CF slot.

Suggested list price $449
The 4150 and 4155 have different model numbers because HP uses different model numbers to track sales in consumer vs. business channels. Both come with a cover pack iPAQ case (canvas, not a very nice one), USB cradle, charger, one battery, an extra stylus, software CD and manuals.

The iPAQ 4350/4355 is a 4150 with an integrated thumb keyboard. That unit is one inch longer and costs $50 more.



Display: Transflective TFT color LCD, 64K colors, Screen Size Diag: 3.5", Resolution: 240 x 320.

Battery: Lithium Ion Polymer rechargeable. Battery is user replaceable. 1000 mA. 1800 mA extended battery available for purchase.

Performance: Intel XScale PXA 255 400 MHz processor. 64 MB built-in RAM (55 megs available). 32 MB Flash ROM with 2.85 megs available in File Store for your use.

Size: 4.47 x 2.78 x .53 in. Weight: 4.67 oz.

Audio: Built in speaker, mic and 3.5mm standard stereo headphone jack. Voice Recorder and Windows Pocket Media Player 9 included for your MP3 pleasure.

Networking: Integrated WiFi 802.11b (also supporting LEAP) and Bluetooth.

Software: Pocket PC 2003 Premium operating system (aka Windows Mobile 2003). Microsoft Pocket Office suite including Pocket Word, Excel, Internet Explorer, and Outlook. Also, Terminal Services, MSN Instant Messenger for Pocket PC, MS Reader and Voice Recorder as well as handwriting recognition. 3rd party software: Westtek ClearVue Suite, F-Secure FileCrypto Data Encryption, Colligo Personal Edition, Adobe PDF Viewer, RealOne Player for Pocket PC, iPresenter PowerPoint converter, MobiMate WorldMate. ActiveSync 3.7 and Outlook 2002 for PCs included.

Expansion: 1 SD (Secure Digital) slot, 4 bit data bus, supporting SDIO and SDIO Now!. Can NOT use iPAQ expansion sleeves.


Back to Home Questions? Comments? Post them in our Discussion Forum!