I found another app called “Deltachat” in Apple’s “App Store” and I’m wondering if it’s legal.
That’s the company behind it:
while the code can be used by everyone following the respective open source licenses, the name “Delta Chat” is protected legally, DPMAregister | Marken - Registerauskunft - this is needed and helpful for various pragmatic reasons.
for the issue at hand - thanks for the reminder - we investigated at some point already, but things got stuck
Beware that in certain jurisdictions, you may lose your trademark if you fail to litigate those who infringe your trademark in a timely manner.