Absolutely improved, HOWEVER I am VERY strict with it and have self control, B"H.
Most people do not and I would definitely NOT recommend a smartphone for them. It is too easy to get hooked on whatsapp and chat groups, facebook, twitter, INSTAGRAM and games as well as checking emails, texts, and forums (like ddf). Videos and movies are also time wasters.
The only thing I do on that entire list is check ddf once in a while and texting a few family members once in a while for information.
I have very few apps on my phone. I mainly use it for WAZE, the enhanced camera, and the enhanced "smart" aspect for phoning, essentially a glorified flipphone. I also use it for looking up information (phone numbers, addresses, and hours).
I think it is a matter of who is in control, you or the phone. Once the phone controls you and even more if you become dysfunctional in your daily life...that is when you know the smartphone has to go. I understand why rabbanim have assured it lchatchila.