Well, it turned out that starting with Android 9, the OS will automatically block any request send under http. The workaround (if you don’t want to implement https on your servers) is to allow http requests for an specific domain or for any domain, editing the resources/android/xml/network_security_config.xml
file on your Ionic project.
a) To allow http for an specific domain, add an entry like this for each domain:
<domain-config cleartextTrafficPermitted="true">
<domain includeSubdomains="true">YOUR_DOMAIN</domain>
</domain-config>
b) To allow http access for any domain, add this entry:
<base-config cleartextTrafficPermitted="true"/>
Hope this helps to anyone dealing with this problem.