Not everyone can afford a separate computer or tablet for each member of the family, so you have to learn to share. It's not that difficult, as long as you set things up right and are willing to cooperate.
Between the two of us, my wife and I share a PC, a Macbook, an iPad Mini, a TV, a portable hard drive, and odd gizmos such as pen drives, power banks and headphones. Over the years, we have figured out how to do this so that neither is left without something they want or need at any moment.
It All Starts With Communication
Like with any social interaction, communication is the key to sharing gadgets in a harmonious way. When we were newly married, I was quite protective of my PC and needed things "just so", but simply talking to each other about why I wanted certain things and why she wanted certain others helped sort out our differences.
Being vocal is an important part of the process, you can't just expect your partner to psychically know what you want. For example, we don't have a superfast broadband connection, and we share the line, so if a video is streaming too slowly, we just ask each other if anything we are doing is taking up bandwidth. Then it's just a simple exchange of knowing how much time that bandwidth will be taken up for, so the other person can adjust their time accordingly. And if the other person needs it in an emergency, have the flexibility to pause whatever you are doing.
Pay Attention to "Externals"
My wife is much shorter than I am, I'm much fatter than she is. It would be crazy if I set up a high desk for the PC and she bought a thin chair. Just like you share the gadgets, you also share the things around the gadget, so you need to make sure these "externals" are something you are both comfortable with.
A lot of this happens when you are setting up gadgets, like the height of a television set or buying a new keyboard and mouse. Don't make it one person's responsibility to buy or install these things; a collective decision during the initial setup requires some coordination (and probably some arguments), but it's well worth it in the long run.
Prime The Device For The Next Person
The annoyance of sharing a gadget is most evident when you use it right after the other person has. To make sharing easier, prime the device for the next person — it takes the pain out of the pickup process.
Case in point: I dual-boot between Ubuntu and Windows, preferring Ubuntu most of the time. That's partly because Ubuntu runs faster on my machine and partly because I like the interface. But my wife is used to certain software on Windows and didn't want to move away from it. I'm now mindful of booting into Windows when I am done using the PC, and she boots into Ubuntu when she's done.
You could do this for any gadget. For example, when you are done using a tablet, a simple process of closing all the tabs can help the other. Or unpairing your phone from the Bluetooth speakers when you are done.
Create Dump Folders
If a gadget hasn't been primed to be passed on, you can't always ask, "Hey, is this unsaved file you left open important?" An easy solution is to have dump folders labelled with each other's name on the desktop. If you find an unsaved file, photo or anything that looks important, Save it there. Similarly, for web browsers, get a session manager and save the session by labelling it with the date and time you closed it.
This way, all of the data isn't lost and you avoid the confusion over where you saved the document that was open. It's always in the dump folder. Periodically, go to your respective dump folders and clean them out.
Share Everything with Multiple Accounts and Profiles
It only makes sense to have multiple profiles set up for commonly used programs and apps. And split anything that can be split up.
Hard drive space is a prime example. It's simple maths, so either add separate hard drives or partition the disk into space for each of you. It's a good idea to keep a third "common" space for items you both use, like your music collection or photo albums. If more space is needed there, you equally proportion it from your respective hard drives.
Of course, you should set up multiple profiles wherever it makes sense. Like I already mentioned, multiple OS user accounts aren't convenient for us because we share programs, licences and software profiles. But there are always things like Chrome or Dropbox. Find out how you can make multiple profiles in these must-have programs and install it.
Look for Alternatives
The solution isn't always to share or set up multiple accounts. Sometimes, the easier way is to let one person have that little space and the other looks for an alternative. For me, there's not much of a difference between using Google Drive or Dropbox for online storage, so I just switched all my cloud data to Google Drive. She gets to use the default Dropbox account on all the gadgets now.
It's not just about software either. For instance, if one person wants to carry the shared micro USB charger with them, the other can take the power bank.
Sacrifices and compromises are a part of being in a relationship, and it shouldn't be any different when it comes to shared technology. Once you start looking for alternatives, you will be surprised by how many there are.
Even though the gadgets are shared, it's healthy to have it "belong" to one person and the other person borrows it. For example, the Macbook is mine, the iPad is hers, but we both share the gadgets. The good thing that comes out of this is that I am ultimately responsible for the Macbook and my wife makes sure the iPad is running smoothly.
Gadgets require upkeep so having one person in charge ensures updates are installed, the machine is cleaned regularly, and other general hygiene measures are taken care of. You can't have both parties thinking "Oh, he/she will take care of it."