Bandwidth Lab: Network Tester

Bandwidth Lab lets developers and testers see how
their apps behave on slow, unstable, or broken
connections, right on a real Android phone. No
root, no proxy setup, and no external server.
Pick a network profile, choose which apps to
affect, and tap Start. Bandwidth Lab limits
bandwidth and adds latency, jitter, and packet
loss to real traffic, so you can reproduce
bad-network bugs in seconds.
READY-MADE NETWORK PROFILES
• Fast 4G, Patchy 4G, 3G, and 2G / EDGE
• Café Wi-Fi with spiky latency
• Choppy Call for real-time audio and video
testing
• Upload Bottleneck: fast downloads, crawling
uploads
• Lift Dead Zone with repeated short outages
• Basement, Barely Connected, and Offline
SCENARIOS THAT CHANGE BY THEMSELVES
Play a timed sequence of network conditions on a
loop:
• Lift ride: good signal, dead zone between
floors, recovery
• Metro commute: station coverage, tunnel loss,
blackout, next platform
• Train journey: fast handovers between towers
• Call breaking up: a call that slowly falls apart
BUILD YOUR OWN PROFILES
Set every parameter separately for upload and
download:
• Bandwidth (kbps), or leave it unlimited
• Latency and jitter (ms)
• Random packet loss (%)
• Repeating outages: drop all traffic for X ms,
then pass it for Y ms
TARGET SPECIFIC APPS
Throttle only the apps you are testing, or every
app on the device. Your other apps keep their
normal connection.
LIVE SPEED GAUGE
Watch real download and upload throughput against
the active profile's limit while you test. Change
profiles while throttling is running and they
apply instantly.
ALSO INCLUDED
• Manual control with quick sliders
• Ongoing notification with a Stop button
• Light, dark, and follow-system themes
WHO IT IS FOR
• Android, web, and game developers testing
loading states, timeouts, retries, and offline
handling
• QA teams reproducing bugs reported on poor
networks
• Anyone checking how video calls, streaming, or
uploads cope with bad connections
HOW BANDWIDTH LAB USES THE VPN
To shape network traffic, Bandwidth Lab uses
Android's VpnService to create a VPN that runs
entirely on your device. Traffic from the apps you
choose is passed through the app on your phone,
slowed down or dropped according to the active
profile, and then sent on to its original
destination.
• There is no remote VPN server; your traffic is
never sent to us.
• The app does not record, inspect, or store your
traffic or browsing activity.
• It does not hide your IP address, bypass
restrictions, or show ads.
• The VPN only runs after you tap Start, and you
can stop it at any time.
PRIVACY
No account, no analytics, no ads, and no data
collection. Your profiles and settings stay on
your device.
GOOD TO KNOW
• Requires Android 11 or newer.
• Android allows only one VPN at a time, so other
VPN apps must be turned off while throttling.
• While throttling is active, IPv6 traffic is
blocked (apps automatically use IPv4) and ping
(ICMP) does not work.
• Speeds are measured in kbps and include packet
headers, so download speeds appear slightly lower
than the configured limit.