Got it, let's tackle this problem step by step. You want to throttle both your Android phone's own internet and any devices connected to its hotspot to a specific speed like 40KB/s—here are reliable ways to make this happen:

If your phone isn't rooted, these apps use a local VPN layer to manage and limit network traffic, which works for both your device and hotspot-connected devices:

• NetGuard: This is a trusted no-root firewall with built-in speed throttling capabilities:

  1. Install NetGuard from the Google Play Store.
  2. Open the app and grant the required VPN permissions (it only creates a local VPN to route traffic, no external server connection).
  3. Tap the three-dot menu in the top-right corner, then select "Settings".
  4. Scroll to the "Traffic control" section and toggle it on.
  5. For your phone's apps: Return to the main screen, select individual apps you want to limit, tap the speed limit icon, and set download/upload rates to 40KB/s each. For global control, set the default limits in the traffic control settings.
  6. For hotspot traffic: In the settings, find the "Hotspot" option and enable traffic control for it. Set the global download/upload limits to 40KB/s, and this will apply to all devices using your hotspot (including your own phone).

• Speed Limit Lite: A lightweight app built specifically for speed throttling:

  1. Install the app, open it, and allow the necessary VPN access.
  2. On the main interface, use the sliders to set your desired download and upload speeds (40KB/s for both).
  3. Toggle on "Limit Speed"—this restriction will apply to all network traffic on your device, including any devices connected to your hotspot, since all traffic routes through the app's VPN.

If your phone is rooted, you can get more granular control by modifying system-level network settings:

• Magisk Module + NetSpeedLimiter:
  1. Install the "NetSpeedLimiter" module from the Magisk Repository.
  2. After installation, open the module's settings panel and set the global download and upload limits to 40KB/s. This will restrict all network traffic, including hotspot connections, at the system level.
• System Tuner Pro (Root Required):
  1. Open System Tuner Pro, navigate to the "Network" tab, then select "Bandwidth Limiter".
  2. Enable the limiter, then set the global download and upload rates to 40KB/s. This applies to all network interfaces on your device, so hotspot-connected devices will inherit the same speed restriction.

• When using no-root VPN-based apps, make sure other VPN services are disabled—they can conflict and prevent the speed limiter from working correctly.
• Always test the speed after setting up the limit: Use a speed test app on your phone and a device connected to the hotspot to confirm the speed is locked at 40KB/s.
• Some apps might have slightly different interfaces, so if you don't see an option right away, check the app's help section or settings menu thoroughly.

内容的提问来源于stack exchange，提问作者pankaj