Menu bar system monitors have a cost nobody talks about. To draw a CPU graph in the menu bar every second, the monitor has to sample the CPU every second, forever, whether or not you are looking. The thing that tells you the Mac is busy is itself a small permanent source of busy. Droppy's System Stats droplet starts from the other end: sample only while the card is on screen, and show enough history that a glance still tells the story.
Sample while visible, never in the background
This is the design rule that decides everything else about System Stats. Open the shelf and the cards start sampling at the interval you set. Close it and they stop. There is no menu bar graph because a menu bar graph would need permanent sampling, and permanent sampling is exactly the drain a monitor should not add. The Mac guide to making a Mac feel fast has a longer list of small always-on things that add up; this droplet is built not to be one of them.
What you lose is a graph you can watch out of the corner of your eye all day. What you gain is a monitor that costs nothing until you ask, and a history graph that, because it covers the last stretch of samples since you opened the shelf, answers the question you actually had: is it busy right now, and was it busy a moment ago.
Six stats, two cards, or Superstats
Total load as a percentage, with the graph showing spikes as they pass. The first card most people pick, and the one that tells you an export or a build is still running.
Memory in use. On an 8GB Mac this is the card that explains why things feel slow, which is the whole argument in is 8GB enough in 2026.
Graphics load. Useful while rendering, running a local model, or wondering why the fans came on during a video call.
Disk activity and space. The card to watch during a big copy, a Time Machine backup or a sync.
Charge and drain. The history graph shows the slope, which is a better answer to how long have I got than a percentage alone. The battery guide explains what the numbers mean.
Up and down throughput. The card that tells you whether the upload is moving or the Wi-Fi has quietly fallen over.
Pick two for the shelf, or switch on Superstats and see all six at once.
Weather, beside the vitals
Weather is its own droplet since 15.0 beta 3, and it lives on the same shelf. Current conditions, temperature and an hourly outlook, either for a fixed city you choose or for the Mac's automatic location. Pick a card style, dynamic, dark or Liquid Glass, and set how often the forecast refreshes. An optional chip puts the current conditions on the lock screen, next to Now Playing and the timer cards described in the lock screen post, so the answer to do I need a coat is there before you log in.
| Menu bar monitor | Activity Monitor | System Stats | |
|---|---|---|---|
| Where | Menu bar, always | A window you open | The shelf, when you open it |
| Sampling | Constant | While open | While visible |
| History graph | Yes | Yes | Yes, rolling |
| Battery cost when closed | Some, all day | None | None |
| All six at once | Depends | Across tabs | Superstats |
| On the iPhone | No | No | Snapshot per sync |
On the phone
Pair Droppy for iPhone and both droplets appear in the At a glance group. System Stats on the phone is a snapshot per sync, not a live graph, for the same reason the Mac droplet does not draw in the menu bar: streaming a live graph to a phone would cost the Mac's battery for a number you look at once. Weather shows the Mac's forecast in the phone's units. Both can sit on the iPhone Home Screen as widgets, which is where the snapshot makes the most sense: a glance at the phone tells you whether the render finished.
Setting the interval
The sampling interval is adjustable. A short interval makes the graph responsive and is fine while the shelf is open for a few seconds. A longer one is gentler if you tend to leave the shelf open while working. Since the sampling stops the moment the shelf closes, the setting only ever governs the time you are actually looking, which is the only time it should.