Q. If I want to send push notification to my phone, which one should I use?
A. Both Amazon SNS and Amazon Pinpoint, support push notification feature and I normally like classifying them as "Mobile Push Messaging" tools however they differ in mechanism as discussed below.
The major difference between Amazon SNS & Amazon Pinpoint is addressed by the Pinpoint FAQ
Q: I already use Amazon SNS or Amazon SES. What do I gain by switching
to Amazon Pinpoint?
In typical Amazon SNS and Amazon SES use cases, you have to set up
your application to manage each message's audience, content, and
delivery schedule. These same features are built in to Amazon
Pinpoint. With Amazon Pinpoint, you can create message templates,
delivery schedules, highly-targeted segments, and full campaigns.
Some of the key features offered by Amazon Pinpoint (i.e currently not offered by Amazon SNS) are:
Hope this helps