What is a subscription service?
Similar to, for example, a magazine subscription. The user is billed to receive recurrent content or services. A subscription text service is initiated when the end-user specifically registers by sending a start keyword. In some cases, a double opt-in is required and the end-user will be prompted to respond with an OK or YES or something similar to confirm. After registering the end-user will receive content and be charged according to the frequency of the subscription service which can be daily, weekly, or monthly. The end-user is de-registered when they send STOP.

Can I have a keyword made up of more than one word?
Yes.

Is a hotline really necessary?
In almost all countries it is a requirement of the mobile network operators or the relevant consumer regulatory or ethics council. As such, a service without a customer service hotline will not be approved.