Then we get into the problems...
There was no good way to bulk maintain pictures. Horrible. Lists? They didn't work. Half the time the email wouldn't be sent out to the group after I shared something. Fail. So, the last time I tried to use it - and realized that nobody got what I sent out, I spent an hour manually deleting every file in my account (since, again, there were no bulk interactions). On top of that, there was no way to simply delete my account.
Kicksend was good in concept, but execution and reliability of it working was one of the worst of any apps I've used in the past few years. I finally ended up switching to a Pro Flickr account and just share things via Guest Passes. Works as expected.
Kicksend was something I really hoped worked well, but all it was to me ended up being a pretty UI that I couldn't trust to work at all. I would have paid for an account had it - since I really did like the interface.
The photos I usually want to print are almost never ones taken on my phone. And because the photos I actually send to people are from my camera I end up using my PC and just upload them to the company and choose the location. Costco, Walmart, Target all offer the ability to print at various locations.
I guess I don't see the benefit here. Driving to the store is the inconvenience in the end. That's why people attach photos or upload them on Facebook instead these days. Perhaps if it automatically snail-mailed the photo to a family member it would be more useful. But even my 70+ year old grandparents prefer I email them photos now anyway.
Edit - Just to add some context, I'm a father with multiple kids with parents and grandparents who demand photos of them every day. :)
I haven't used the app yet, I'm about to, but what's the advantage over just emailing the photos to the grandparents?
But over the years I've come to the realization that attaching photos is still the best way to share photos with grandparents.
Scenario 1 (attach to email)
Grandpa receives an email with an automatically generated thumbnail and clicks the thumbnail to see the larger version.
Scenario 2 (everything else)
Grandpa receives an email with a link. The thumbnails probably don't show up because images are turned off by default and that's how Grandpa rolls. Grandpa clicks the link which opens a new tab and shows similar thumbnails to scenario 1. Grandpa clicks to see a larger version.
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Granted, you can provide a bunch of additional value (like ordering prints and whatnot) in scenario 2. But it comes at a very steep cost.
Disclaimer, I'm a founder of OpenPhoto and work about 30 yards from the Kicksend team. I personally use their app and think they're on to something. But I'd be lying if I didn't say it's a challenging road (for them and us).