SaaS Metering helps ISVs to meter the usage of the software and charge as per the usage. Techcello provides Metering API to help you to audit the number of transaction/usage consumed by the Users/Tenants. ISVs can use this metered data to charge their customers. For example when you want to define your subscriptions like the one below, you need to meter and limit the number of users created by each tenant in the system(Refer the below screenshot)

If your application pricing model is not based on usage based pricing then it is not mandatory for enabling the Metering API.