A free app for Android, by Prosults Studio.
This application is a tool for all people who are interested in learning the correct spelling and grammar of the Dutch language.
What makes it special is that it contains a database with 20,000 Dutch words. This is the most relevant database with regard to spelling and grammar.
The database is sorted in three categories: nouns, verbs, and adjectives. This makes it very easy to find the correct spelling and grammar of a word.
The application has three options: you can choose a quiz of between 10 and 50 words in three difficulty levels, indicated by dots. You can also choose the option to look up the correct article for a noun or search and browse through the list of 20,000 Dutch words.