Hello,
We been working hard to come up with our Strongswan IOS native APP
you can download the app from Apple App store ( Brooog VPN )
https://apps.apple.com/gb/app/brooog-vpn/id1542583818
the app will allow you to add as much server as you want with no restriction for free,
you need to setup your Strongswan Configuration correctly to work.
here is the configuration you need to make your vpn works on IOS.
conn IPSec-IKEv2
leftauth=psk
rightauth=eap-mschapv2
rightsendcert=never
eap_identity=%any
auto=add
if you need any help, contact us