Complex sentence: Many mobile apps can prevent robocalls with a user generated blacklist and in the UK BT operates a service for landlines called Choose to Refuse which allows customers to block up to 10 phone numbers of their choice for a monthly fee.
Split into simpler sentences: Many mobile apps can prevent robocalls with a user generated blacklist. In the UK BT operates a service for landlines called Choose to Refuse which allows customers to block up to 10 phone numbers of their choice for a monthly fee.