I am looking for an app that I can use to PROVIDE me with math problems for practice and to stay fresh on various subjects in mathematics. This includes all levels of math (from low grade school to differential equations, linear algebra, ect). These practice problems would be random and new each time so that they continue to challenge me and provide an endless supply of practice.
That is the ideal, if this is not realistic I would settle for a handful of apps that provide most (if not all) of the subjects for practice examples. I am finding many options for subjects up to basic grade school math and one that goes up to precalculus but I would like to practice the upper level problems as well.
Note: What I mean by "provide me with problems" is if I were to "generate" a problem for a particular subset of mathematics I would be presented with an appropriate problem that I would be able to solve and put in an answer to be given feedback for. This app does not need to provide a calculator or any math solving tools/software.
Thank you.
My top picks:
Mathcounts trainer: It gives you lots and lots of problems from MATHCOUNTS middle-school competition, and it lets you draw in the app, so you can write your work down their without going through lots of pencils and papers.
Alcumus: This isn't really an app, but its a website you can access on mobile so what's the difference? It gives you problems more difficult than the ones in MATHCOUNTS. I believe that it covers problems in Prealgebra, Algebra, Number Theory, Counting/Probability, Geometry, Intermediate Algebra, and Precalculus. It also lets you pick a difficulty as well. You can access it here https://artofproblemsolving.com/alcumus.
You can also find many other resources here https://artofproblemsolving.com/resources.