Samsung Galaxy S6 Active has a strong reception and good in-call audio. If you run the Adapt sound feature you it can tune the call sound when you use a headset. The in-call equalizer for the phone's earpiece is gone though.
The dialer has a Material Design paintjob. Smart dialing (searching through contacts by using the keypad) and speed dialing (assigning a contact to a number on the keypad) are on board. Video calling is also natively supported, not that many people use it.
Additional tabs in the app show the call log, favorite contacts and a list of all contacts. You can use the separate Phonebook app for that.
The Phonebook is a list of contacts with a search field and an alphabet index. The contact info card has been cleaned up and shows the contact image (you can swipe down to view it fully), below that are the phones and emails with quick buttons to call/send message.
Here you'll also find the latest messages and calls with that contact. The View more toggle displays all the additional info. You can swipe left to call a contact straight from the list, right to send them a message.
The built-in call rejection feature lets you block calls from certain numbers or all numbers not in your phonebook. Do not disturb mode can be scheduled on select days and during certain periods of the day. You can set it to make an exception for certain notifications, including allowing only calls from your favorite contacts.
Samsung is sticking to a single loudspeaker setup with the Galaxy S6 Active. This time, the component is placed on the back of the device, not on the bottom like in the regular model.
By default the Messages app has a clean looking UI, but you can customize font size, backgrounds and speech bubble style. The app shows a row of priority contacts, below that is the list of all conversation threads. You can use pinch zoom to change the font size in a conversation thread.
The Album option collects all photos and videos shared in the given conversation thread. The Attach button shows the most recent photos and videos so you can pick them easily, but below that are additional options for other multimedia.
A built-in spam filter weeds out messages from select numbers or containing certain phrases. You can also schedule messages to be automatically sent later (so you don't forget).
The Samsung-modified Email app looks almost identical. The top row is a shortcut to show emails only from just priority contacts or you can view a combined inbox if you have multiple accounts added.
The Gmail app also handles multiple accounts - even ones not on Gmail - and adheres more strictly to Material design principles. Add push notifications and we end up using it more often than the Email app.
The Samsung keyboard features a dedicated numbers row. You can tweak the size of the keyboard slightly, making it taller or shorter and if you are okay with a tiny keyboard, you can use the small floating one. You can add text shortcuts (so 'brb' gets replaced with 'be right back') and there's predictive text.
It can update its database with popular words weekly and learn from your messages and contacts. Swiping can be set to move the text cursor or as an input method.