Memory Expansion Cards
One over-riding point that applies to both platforms is that the device should have the ability to accept a memory expansion card. Medical resources are often quite large and you will soon run out of space with a memory card. Avoid devices that do not have this ability.
Until recently, this ruled out all of Palm's own devices. Only the latest Palm machines provide memory expansion capability with an SD card slot. Other manufacturers all provide this already.
All memory cards are non-volatile - this means that they are immune to flat battery situations. They tend to run very slightly slower than the main memory in the device but this is not noticeable in real life situations. They have no moving parts and are really quite robust.
Types of Memory
 | Compact Flash (CF) |
| Secure Digital (SD) |
| MultiMedia Memory Card (MMC) |
| Springboard |
| Sony Memory Stick |
| SmartMedia |
| PC Cards (PCMCIA) |
Compact Flash
The commonest and most widely used format. Comes in three sizes: Type I, II and III (only affects the thickness). No PDAs use Type III cards - the thickest. Comes in capacities from 8MB to 1GB. All PocketPCs, along with the HandEra (a Palm OS device) accept these.
Secure Digital
Up and coming format. Only one size - much smaller than CF. Capacities 8-128MB. Only type supported by Palm's devices. Also used by HandEra, Compaq and Toshiba.
MultiMedia Memory Card
Very similar to SD (its predecessor). Devices that read SD cards will also read MMC cards. The reverse is not always true.
Springboard
Proprietary format for Handspring. Looked promising but has not really taken off as much as they had hoped.
Memory Stick
Proprietary format for Sony (Betamax redux?).
SmartMedia
Not used by any PDAs.
PC Cards
Originally known as PCMCIA (People Can't Memorise Complicated Industry Abbreviations?) cards, they are quite large. Originally designed for laptop use, they are a bit big for most PDAs. Only Compaq and Hewlett Packard PocketPCs can accept them, with additional sleeves. Not used much for memory but still used for more demanding tasks such as wireless networking, GPS and some esoteric hardware add-ons.