If you have some time on your hands, there are a few new things to do on Akala Island, and Melemele Island as well.
Gift from Burnet
Back at the 3rd floor of the Dimensional Research Lab in Heahea City, you can speak to Burnet in her room to receive a Reveal Glass . This key item will transform Thundurus, Tornadus and Landorus into their Therian Forme and back again. Rather fitting since the Therian forms were introduced in Dream Radar.
Towards the north-west corner of Royal Avenue, near the Battle Royal Dome, you’ll find a trainer and his Incineroar who are in a bit of a pickle. If you show them the TM for Acrobatics, obtained in the latter half of Route 15 on Ula’ula Island, you’ll be rewarded with a Power Belt . This held item temporarily reduces Speed, but promotes Defense growth
The next time you visit this same corner, there will be a trainer with a Machamp instead. This time, you need to hand over a Coba Berry, which can be randomly obtained from the berry trees in Poni Wilds on Poni Island. Your reward is TM08 Bulk Up , which raises Attack and Defense at the same time, perfect for brawler types.
Meal with Olivia
If you go to Mallow’s restaurant, along the west side of Konikoni City, below Olivia’s shop, you can order food from the entrance. Choose the last meal, the "Special Z-Set" and Olivia will visit the restaurant. She’ll pay for both of your meals and you’ll also get 4 Heart Scales at the end, instead of 2. This event can be repeated the next day.
Be Wary of the Bear
During the day, if you visit the Hau’oli City Shopping Mall, next to the Pokémon Center, you can watch a Bewear costume show in the north-west corner of the mall. Amid the excitement, a wild Bewear crashes the show and you’re given the chance to capture or defeat it. Afterwards you’ll receive a Max Potion for your bravery.
Hypnotic Crime Scene
Should you return to the Hau’oli City police station, you’ll find Captain Ilima interrogating a trio of Hypno suspects. You can’t make this up. When prompted, pick any answer to battle the corresponding Hypno suspect. Each Hypno has different moves, although the Hypno with Psychic only knows Confusion, strangely.
After you catch or defeat the Hypno, you will receive a Big Nugget from Ilima. This can be sold to Poké Marts for a high price or kept in your private collection.