Ask HN: "Time zone" tag feature in communication apps

[os7borne]

Recently, I've had to schedule calls with founders and investors from across the world South East Asia to Europe to Latin America. While scheduling, converting time zones is always a task - switch app, check, agree.

Is it difficult to build a feature within communication apps (Email, Chat, DM's etc.) to have a "Time Zone" tag? Similar to a contact tag in email, for example.

The "Time Zone" tag can automatically display the local time of sender or receiver. I know there are tools that can convert time for you and use additional extensions etc. But why not bake it as a feature within such communication apps as scheduling is so important?