Privacy Policy for iPhone

Last updated: 2026-09-12 / Applies to: Denpa for iPhone

This is the privacy policy for the iPhone version. The permissions work differently from the Mac version, so the pages are separate. Privacy policy index / Mac version

This is a translation of the Japanese privacy policy. If the two differ, the Japanese version applies.

Denpa is an iPhone app for measuring the state of your Wi-Fi and internet connection and narrowing down where a problem is. This page explains what information the app handles, and what network traffic measuring generates.

What never leaves your device

Results, location names, and notes are stored only on your device (using standard iOS storage).
Nothing is sent to the developer or to a third party. There is no analytics, advertising, or tracking.
Location is never recorded or sent. (See “Permissions the app asks for” below.)

What it connects to in order to measure

Measuring speed and response time cannot happen without real network traffic. The destinations are listed below.

Purpose	Destination
Speed test (download and upload)	Cloudflare (`speed.cloudflare.com`). Can be changed in Settings to Linode (Singapore), OVHcloud (France), or Vultr (Tokyo); those three are download only
Response time to the internet	1.1.1.1 (Cloudflare public DNS)
Checking whether the connection requires a sign-in	captive.apple.com (Apple’s connectivity check page)
DNS lookup time	Looks up `www.apple.com`, `www.google.com`, and `www.yahoo.co.jp`
Response time to the first device	An address on your own network, such as your router
Page measurement (the Page screen)	The site at the URL you enter. Like a browser, it connects to that page and to the external resources the page loads. Where it connects depends on what you enter; the app never chooses the destination. If you do not use this screen, none of this traffic occurs

These destinations see your IP address, because they are the other end of the connection (this is unavoidable on the internet). The app does not attach any information that identifies you.

About the Page screen

The app never saves the URLs you enter, the pages you view, or their content. Nothing is kept in History.
The cache is cleared before every load, so no page data remains on your device.
The traffic is the same as a browser’s, so to the site you connect to it looks like ordinary browsing (including cookies being sent and received). The app does not control this.

How much data a measurement uses

You can choose in Settings how much data one speed test uses. Download and upload use the same amount.

Setting	Each direction	Total per run (on a server that supports upload)
Small (S)	5 MB	10 MB
Medium (M, default)	20 MB	40 MB
Large (L)	30 MB	60 MB

The app itself also tells you to be mindful of this on a cellular plan.

Permissions the app asks for (two)

Permission	What it is for
Location (while using the app, precise)	Used only to show the network name (SSID) of the Wi-Fi you are connected to. Location is never recorded or sent. iOS requires location permission to read the SSID; the location itself is not used
Local Network	A permission iOS requires in order to communicate with devices on the same network, such as your router

The app works without either of them.
Without Location, the network name (SSID) is not shown.
Without Local Network, every measurement still runs (including the response time to the first device).

Contact

For questions about this policy, write to the address below.

highislandtec@gmail.com

Replies may take some time.

For how to use the app, or to report a problem, see the support page.