Very Slow Android App (using Mobile 5G or LTE) on new Server Setup

Hey there,

just Setup a new Rocket.Chat Server on Ubuntu 22.04 with Snap.

The Server is realized as VM behind another Ubuntu Server which is acting as Reverse Proxy.
DNS and SSL is Setup and Rocket.Chat is running and working fine with Browser and Desktop App.

Using the Android App in Wifi (same Network as the Server) it is very fast and perfect.
But when i’m on the road (5G or LTE) the App is extreme Slow. Connecting to the Server needs 20 Seconds.
Posting a Comment 15 Seconds and so on…
Posting an Image takes ages…

Is there anything i can do to speed this up?

Server Setup Information

  • Version of Rocket.Chat Server: 5.2.0
  • Operating System: Ubuntu Server 22.04
  • Deployment Method: Snap (also tried Docker on Synology, same behaviour)
  • Number of Running Instances: 1
  • DB Replicaset Oplog: Enabled
  • NodeJS Version: 14.19.3 - x64
  • MongoDB Version: 4.4.15
  • Proxy: apache (on another Maschine)
  • Firewalls involved: not for testing

Reverse Proxy Settings

 <VirtualHost *:80>
 RewriteEngine On
 RewriteCond %{HTTPS} off
 RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI}

 RewriteCond %{SERVER_NAME}
 RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]

  <VirtualHost *:443>

LogLevel info
ErrorLog /var/log/apache2/rchat_error.log
TransferLog /var/log/apache2/rchat_access.log

    <Location />
    Require all granted

RewriteEngine On
RewriteCond %{HTTP:CONNECTION} Upgrade [NC]
RewriteCond %{HTTP:Upgrade} =websocket [NC]
RewriteRule /(.*)           ws://$1 [P,L]
RewriteCond %{HTTP:Upgrade} !=websocket [NC]
RewriteRule /(.*) $1 [P,L]

ProxyPassReverse /
Include /etc/letsencrypt/options-ssl-apache.conf

SSLCertificateFile /etc/letsencrypt/live/
SSLCertificateKeyFile /etc/letsencrypt/live/
SSLCertificateChainFile /etc/letsencrypt/live/

best regards and many thanks