This example compares plans that have the same duration and similar monthly payment:
Plan 1: 24 month contract, 30 inclusive talk minutes, 500 texts, 100MB data, payment is 10.50 per month.
Plan 2: 24 month contract, 50 inclusive talk minutes, 25 texts, 250MB data, no handset cost. Payment is 10.99 per month.
The App shows that plan 1 is a little cheaper over the lifetime of the contract but is more expensive for data and talk. It it is better for texting than plan 2. Plan 2 would be better a phone needed for occasional use, plan 1 for someone who needs to sends text regularly.