Weather and water.
Rain, Snow, Fog, Clouds, Mist and Lightning; Falling Water, Splash, Shimmer and Bubbles.
Where: Effects in the dock, then Weather or Water.

Look
Forty effects, made on your phone, not downloaded. Lay one over the whole picture, place it where you want it, and erase it where it shouldn't be.
Android 8.0 and up, 64-bit phones. Not on iPhone yet.

Rain, Snow, Fog, Clouds, Mist and Lightning; Falling Water, Splash, Shimmer and Bubbles.
Where: Effects in the dock, then Weather or Water.

Falling Leaves, Petals, Foliage, Butterflies and Birds; Flames, Embers and Smoke.
Where: Effects, then Nature or Fire.

Starfield, Aurora, Wishing Stars, Fireflies and String Lights; Confetti, Fireworks, Balloons, Hearts and Sound Waves.
Where: Effects, then Night or Celebration.

Sparkle, Dust, Bokeh, Light Leak and Glitter; VHS, Sun Stains, Lens Flare, Rainbow and Energy Orbs; Ghosts and Bats.

Strength sets how strong it looks. Erase brushes it away where it shouldn't be, like rain inside a room. Drag to move, pinch to resize, and pick a blend: Normal, Screen, Add, Multiply or Lighten.
Where: Tap an effect, then Strength, Erase or Remove. Blend lives on the layer.

Snow on a winter street, petals in spring, leaves in autumn.
Confetti, balloons, hearts and fireworks for birthdays and weddings.
Fog in a forest, embers by a fire, fireflies at dusk.
No. They're drawn live on your phone, so they fit any size of picture and work offline.
Yes. Each effect is its own layer, so you can stack them.
Yes. Use Erase and brush it away, with a brush size you choose.
Yes, on photos and on clips.
Overlays is a second shelf of the same effects, grouped into looks like 90s VHS, Mysterious Mist and Gentle Wings.
Swish is on Google Play. Install it, pick a photo, and show it what moves.
Get it onGoogle PlayAndroid 8.0 and up, 64-bit phones. Not on iPhone yet.