Sharing one input device across multiple machines seems like a great thing at face value. If you have a Mac and an iPad (or even two Macs) then Apple’s own Universal Control works fantastically and (usually) without a hiccup. My biggest problem that I have encountered is two devices just not automatically communicating which I have always been able to fix by toggling on and off Universal Control from one of my Mac’s settings.
That’s all well and good but what if you have a Mac and a PC and want to share input devices across the two? If you plan on using one device at a time, a KVM switch will always be the best way to go. Hardware solutions are exactly that – a physical device that connects to two (or more) machines into which your input devices are connected.
What if you’re like me and use a Mac and a PC at the same time? Here are some solutions I’ve tried with varying degrees of success and usability.
VNC into your second computer.
How I would implement this is run VNC server on my PC and then connect from my Mac to the PC. This works best for me if I have multiple monitors running and then dedicate a screen to the VNC session. The benefits to this, for example, is that if your secondary machine is a desktop and your primary machine is a laptop, then you can access your secondary machine from anywhere while only carry one computer. My VNC platform of choice is Real VNC and I’ve had no issues establishing a connection from anywhere. The drawback to this is latency. If I’m connecting over my local network, latency is much less of an issue but when I’m out and about then I am at the mercy of whatever internet connection I may be using. I’ve also connected to my phone’s 5G hotspot and even though my cellular connection may consistently give me well over a 100Mb/s transfer speeds, my ping is usually hovering around the 900ms mark which makes doing any sort of sustained work nearly impossible. For things like a quick move of a file, no problem, but the constant latency from keystroke or mouse click to response from receiving machine is unbearable.
In summary, this is a great free solution when working locally but is not reliable (for me, at least) when I want to work remotely on a computer than is stationary in my house.
Use a KVM switch.
I haven’t used a hardware KVM solution for a few years but changes to KVM offerings don’t change very quickly except when the intent is to share a single monitor with a single connection. A cheap KVM switch can be had from Amazon for less than 50 bucks while enterprise-grade solutions can hit eye-watering, multi-thousand dollar price tags. The pros are that there is no latency – your input devices are physically connected to the target machine. The drawback is that you can only use one computer at a time and you (typically) have to manually (with a physical button) toggle between your target machines.
The monitor I use is a Samsung Oddysey G9 with a native resolution of 5120 x 1440 at 240Hz. Cheaper KVM switches don’t support ‘exotic’ resolutions and those that do won’t typically go above 60Hz. Luckily, my monitor has to DisplayPort inputs so I keep one connected to my Mac nad one to my PC and just toggle the source on the display and I toggle the inputs between my machines.
When I want to work, and test code across two machines at the same time, a physical switch just doesn’t fit into my workflow. When I’m done for the day and want to play a game, especially a FPS, a KVM switch works great and doesn’t cause any input lag.
Symless Synergy 3
I bought a license for Synergy all the way back in 2018 and had totally forgotten about it. Perhaps that was a bit of foreshadowing but this piece of software was at the top of the search results when I looked for “share mouse and keyboard between PC and Mac”.
Installing the software is straight forward regardless of platform and I even tried running an old Dell Laptop with Ubuntu in-line with my MacBook Pro and Razer blade to see if their ‘works on all platforms’ meant ‘works on all all platforms at once’. I was surprised but it did. I set my MacBook Pro as the host and connected the Ubuntu machine to the left and my PC to the right. It just worked.
Even though it works as advertised and it works reliably, it wasn’t without its own caveats.
When I have my MacBook Pro sitting next to my Razer Blade 16, it works great. I can have both devices side-by-side and, much like Continuity between two apple devices, the cursor floats between the two screens with no trouble. I can test code on both machines at the same time and all is well in the world.
My Mac is my primary work computer so when I’m working at my desk and have my Mac connected to my external monitor, then I notice hiccups with what I believe is input lag. It’s most noticeable on my PC where I can very clearly see jerkiness when moving the cursor which increases as the cursor accelerates. Input lag from the keyboard is not noticeable but my only “testing” is what I can perceive. Keep in mind, when I am stationary, at my desk, my machines are connected via Ethernet to my home network no network latency should not be a factor. Even so, when I am on WiFi just using my Mac and PC (no external displays) side-by-side, I don’t notice any cursor lag.
I’m going to dig into this further and plan to post a more in-depth review of Synergy 3 so stick around for that coming soon.
There is no “one size fits all” solution for me.
What I have determined is that each solution fits a different use case. When I’m at home working on my ultrawide monitor, a VNC session sharing half of my display works great. When I have both machines present then placing them side-by-side and using Synergy 3 is great. When I’m at my desk and want to switch to my PC for a gaming session, then a KVM switch with my keyboard, mouse and controller fixed in place fits the bill.
Thankfully, all three of these solutions cost me about 85 bucks. A license for Synergy 3 is $29.99 and the KVM switch I use cost a little over 50 bucks. A personal, 5 device license for RealVNC is free and I’ve used RealVNC for years and have never had an issue aside from maintenance windows on their end.
Your situation is going to be different and some, all or none of what works for me might work for you. If you’ve got a unique scenario or solution, let me know in the comments.