During the course of Homestuck, Dave Strider uses several computing devices to stay in touch with his co-players and the trolls.
Dave's Computer[]
Dave's initial computing device. It looks like a regular, but fairly advanced desktop computer. His wallpaper is from And It Don't Stop, another one of Hussie's comics. Not much is known about it.
Dave's Phone[]
Dave Strider's phone is an item found in Homestuck. Much like John Egbert's PDA, Dave's phone allows him to communicate with his friends using Pesterchum and, according to the icons, allows him to call others, check his email, and use the internet with Hephaestus, his favored browser. It is clearly an iPhone, as the Apple logo is visible on the back. It is usually depicted as an iPhone 3G, though when shown from the front, the plastic antenna band exclusive to the first generation iPhone can be barely seen around the bottom of the device. Compared to a real iPhone, this one can open programs such as Pesterchum as separate windows.
The background of Dave's phone, like his computer, is from one of Andrew Hussie's other comics, And It Don't Stop.
iShades[]
Davesprite combines his iPhone with his sunglasses to make the iShades, a communication device on par with John's Serious Business Goggles. Present Dave also makes this item.
The iShades, sometimes referred to as iGlasses, are Dave's equivalent of John's Serious Business Goggles. They look like his normal sunglasses with an Apple logo in the middle of each lens, and they create a blue glow around his eyes when active.
The iShades are created both by future Dave and alpha Dave. When future Dave prototypes himself, the iShades seem to be the only thing he takes with him into the sprite. Since Davesprite can access Pesterchum seemingly without using a computer, it is implied that prototyping himself while wearing the iShades made them a permanent part of his sprite. When present (alpha) Dave finds the time to mess around with his alchemiter, the iShades are the first thing he creates, as he has already seen Davesprite's iShades.
The iShades are made by combining Dave's iPhone and sunglasses. It is unclear how they are operated, but it is likely to be some kind of hands-free system. When running PesterChum, the iShades are shown to use a voice-to-text converter.
Turntop[]
The turntop is a portable computer, created by alchemizing the Timetables and Dave's PC. It costs 600 Build Grist, 1200 Garnet, 900 Mercury, 300 Gold, and 1 Diamond. It allows him to take his PC with him wherever he goes, a significant upgrade from the iShades as it allows him to operate Sburb. It seems like they are able to be used without hands.
After the Scratch, Dirk Strider's primary desktop computer features the same screen, but is operated with a more regular keyboard.
Dave's wrist communication device[]
In Act 6 Act 6 Intermission 2, Dave is seen wearing a communication device on his wrist, from which he receives a blurry message from Karkat. It is shaped like a green butt, and it was most likely alchemized from one of his bro's smuppets.