iOS 18.0 or later / iPhone, portrait only

Wi-Fi feels slow.
Measure what is happening,
and see where the cause is.

It measures the segment from your device to the first device (your router, or the carrier gateway on a cellular connection) and the segment beyond it to the internet, and shows which side the cause is likely to be on. It can also measure how long a specific web page takes to load. Results stay on your device.

FreeNo in-app purchasesNo ads No accountJapanese / English

Measuring the two segments separately shows whether the cause is inside your home or beyond it.

It measures only when you tap

There is no continuous monitoring. Nothing is measured until you tap Start diagnostics.

Response time

15.6 ms

Jitter

5.9 ms

Packet loss

0 %

DNS lookup

3 ms

Download

54.7 Mbps

Upload

25.1 Mbps

Example results. Values vary with your connection and surroundings.

Connection: Always shows what you are connected to: connection type, IP address, router address, and DNS server. On Wi-Fi it shows the network name (SSID) and the security type; on cellular it shows the network type, in the same place.
Diagnostics: Measures the two segments separately and tells you in plain sentences which side the cause is likely to be on. Findings are listed as Error, Warning, or Information, each with what you can try.
Page: Loads the page at a URL you enter and measures how long the load takes. It shows three values — Load time, Speed, and Transferred — along with a chart of the load over time. The page itself is displayed, and tapping a link in the page measures that URL. The cache is cleared before every load, so measuring the same page repeatedly keeps the conditions identical.
History: Shows saved results by location, as a chart over time and as a list. Measuring the same place repeatedly helps you decide where to put a Wi-Fi extender.

The Connection screen, showing the Wi-Fi network name (SSID) and the security type

What this app cannot do

What the app cannot do matters as much as what it can, so it is stated up front. The same list appears under How to use in the app.

It cannot change your router settings.Its job is to narrow down the cause.
It cannot measure other devices.Everything shown, including every measurement, is seen from that iPhone.
Signal strength (what the bars represent) cannot be shown.Only apps individually approved by Apple can read it.
It is not an app that makes your connection faster.It is a tool for measuring and narrowing down.
The speed shown on the Page screen is not the speed of your connection itself.Page loads are dominated by waiting, so the value comes out lower than the speed of the connection itself. Measure the speed of the connection on the Diagnostics screen. Do not compare the two figures or treat them as the same thing.

Results stay on your device

Not sent

What never leaves your device

Results, location names, and notes. URLs you enter on the Page screen and the pages you view are not saved either. Nothing is sent to the developer or to a third party. There is no analytics, advertising, or tracking. Location is never recorded or sent.

Traffic does occur

Where it connects in order to measure (the main destinations)

The speed test uses speed.cloudflare.com (you can switch to Linode, OVHcloud, or Vultr in Settings; those three are download only). Response time uses 1.1.1.1, the connectivity check uses captive.apple.com, and DNS lookups use www.apple.com and others. On the Page screen it connects to the site at the URL you enter: you choose the destination, not the app. Measuring cannot happen without real network traffic. The full list is in the privacy policy.