Check out https://enterprise.arcgis.com/en/portal/latest/administer/windows/import-a-certificate-into-the-port...
That being said, are you accessing portal with your mobile device over wifi? That is, 100% internal and not exposed to the external Internet. If yes, then self signed certs can probably be used.
If you are looking to take your app outside so it will be connecting through the Internet, things become more complicated:
NOTE: These are broad categories and not specific steps. Your particular environment or situation will most likely require some modification. This information is being provided for conversational purposes only and assumes no liability.
- Make sure all security best practices have been accounted for at all points in the chain.
- Establish a valid domain name. https://www.google.com/search?client=firefox-b-1-d&q=low+cost+domain+names For example https://Dashe.com
- Get certificate for Dashe.com - https://letsencrypt.org/ is good for free 90 day certificates - and apply to your portal web server.
- Point DNS for Dashe.com to your external WAN IP address. Your firewall will come under almost instant probing/attack at this point so make sure all updates are in place, configuration is clean, and you are comfortable that the firewall is capable of standing up to some levels of attack.
- Configure firewall to point to your portal webserver instance so you expose Dashe.com/portal/home
If you are part of an organization that has an IT department, make sure to involve them.
Tom
