Meldfall is free, runs entirely in your browser, and needs no download and no account. Drop an orb, let two matching orbs meet, and watch the chain reaction climb the ladder toward the Cosmos.
If you have played one of the fruit-merging games with a watermelon at the top of the ladder, you already know the shape of this one: the same drop-and-fuse loop, eleven tiers of orbs instead of a fruit basket, and the Cosmos at the end of the climb. It plays the same on a phone as on a desktop - aim with a finger, tap to drop.
Part of Gravity Ledge, a small collection of browser games about things falling.
Two orbs of the same colour that touch fuse into the next one up. There are eleven tiers, from Spark at the bottom to Cosmos at the top.
Only the first five tiers can be dropped. Everything above that has to be built by merging, which is the whole game.
When an orb's centre stays above the red line for about a second, a ten second countdown starts. Merging something below the line clears the danger and the countdown winds back up, so it is a warning rather than a verdict.
Every UTC day every player gets the same orb sequence, so scores are comparable. A new one starts at midnight UTC, and your best for the day is kept on your device.
Yes, there are five skins in the settings panel, from the default Cosmic to Neon and Gem.