Whenever possible, use the following contact methods;
they allow verification to mitigate man-in-the-middle attacks,
have solid security, and reasonable privacy.
Use the keys for each contact method to verify my devices. Note that verification does not verify a person, only their devices, and can be defeated via coercion or other force.
If metadata leakage is an issue for you, you can use the following
contact methods.
Note: These services do not have verification
functionality and will be treated as less secure;
unless you really
need to use these services, use a preferred method instead.
The following contact methods do not utilise end-to-end encryption, or I do not use such functionality; they are suitable for public contact only, including directly and groups. Do not use these methods if confidentiality and/or privacy is required.