SimpleMind Free is an Android app that lets you create your own mind maps using a practical and simple interface where you can directly draw nodes and the connections between them using touch gestures.
Its customization options are limited but still cover basic needs when it comes to creating a mind map, letting you change the word or phrase in each node as well as its color. Likewise, there are automatic visual themes that change the whole map's appearance, including the basic shape and style of the connectors. You can also change the whole map's style in terms of sizes and fonts.
You can save your creations and access them later, although you won’t be able to export them to any external formats. This doesn’t, however, prevent you from taking screenshots of the diagrams you make.