At the price the apps cost, get them both!
No kidding; the cheap price of apps is a blessing. Compare to desktop apps costing typically $30 or more. Apple's App Store has eliminated layers of middlemen (distributors) making it possible to sell these programs so cheaply.
When there are half a dozen apps that serve a purpose I need very much, I won't hesitate to buy several and then compare them. I'm only out maybe $10 for the entire lot! What else can I buy that's that cheap ? A single router bit can cost $50 or more.
When I read user reviews of apps, I'll sometimes come across a review from some ingrate who is downgrading the app (as in, 1 star) because it sells for $0.99 instead of for free.