Why does the WiFi Analyzer only update every 30 seconds?
Because Android will not let it update any faster.
From Android 9 (Pie) onwards the system throttles WiFi scans. An app in the foreground is allowed 4 scans every 2 minutes — one every 30 seconds — no matter how often it asks. Apps in the background get one scan every 30 minutes. The limit was added to save battery, since a WiFi scan wakes the radio and is surprisingly expensive.
PortDroid tells you which of the two you are getting: the WiFi Analyzer’s header shows the scan cadence, and says “every 30s (throttled)” when the system is holding it back.
Throttling is a system setting, not a PortDroid one — no app can turn it off for you, and no app can scan around it. What you can do is turn it off yourself, for the whole device, in developer options. It takes about a minute.
Step 1 — Turn on developer options
Developer options are hidden until you ask for them.
- Open Settings
- Go to About phone (on some phones: System → About phone)
- Find Build number — on Samsung it is under Software information, on Xiaomi under All specs where it is called MIUI version
- Tap Build number seven times
- Enter your PIN, pattern or password if you are asked for it
- You will see “You are now a developer!”
If you already have developer options, skip to step 2.
Step 2 — Turn off WiFi scan throttling
- Open Settings
- Go to System → Developer options (on Samsung, Developer options is at the bottom of the main Settings list)
- Scroll down to the Networking section
- Find Wi-Fi scan throttling and turn it off
That is it. Go back to PortDroid’s WiFi Analyzer, pull down to refresh, and the header will stop saying throttled — the list, the channel graph and the signal graph all start updating every few seconds instead.
PortDroid can take you straight to developer options: WiFi Analyzer → ⚙ settings → Scan throttling → Developer options.
I can’t find the setting
A few things to check:
- Android 8 or older — there is no throttling and no setting. Scans were never limited.
- No “Wi-Fi scan throttling” entry — a handful of manufacturers remove it from developer options. There is no other way to change it; the list will keep refreshing every 30 seconds.
- It is there but greyed out — some work profiles and MDM-managed devices lock developer options. Your IT administrator controls it.
- It turned itself back on — a few OEM “battery optimisation” or “phone care” features reset developer options after a reboot. Turn it off again, and check whether your device has an aggressive power-saving mode enabled.
Does turning it off hurt anything?
It uses a little more battery while you have a scanning app open, because the WiFi radio is woken more often. It changes nothing while your screen is off, and nothing about how your phone connects to networks. Turn it back on when you have finished surveying — the switch is in the same place.
Why does PortDroid want to scan more often?
The WiFi Analyzer is most useful when it reacts as you walk around: finding a dead spot, pointing an antenna, or picking the clearest channel all depend on seeing the signal change as it happens. At one sample every 30 seconds the signal graph covers half an hour in sixty points and a walk around the house registers as two or three readings. Unthrottled, the same walk is a curve.