Somewhat similarly to Total War, this game consists of two main parts - a turn based strategy level, and a turn based tactical battle mode that can be skipped. After a single time I skipped all the battles as the controls weren't particularly easy, it slows the game down a lot as you have lots of battles to fight, and the AI just blobs all its units in one place, so you don't really have much strategy apart from charging all your units into the enemy en masse. Air and naval battles are autocalculated anyway, although if you have two armies and air support you do get to call in air strikes on the battlefield (before your men get too close).
In terms the of the strategy part of the game, this is a fairly simple affair (although you have some flexibility over how simple the economy is), but it mostly works fine. You have limited funds and have to choose what buildings and where - putting your unit recruiting buildings on the borders means you can repair your units directly at the front line in one turn (a week), if you have the cash, whereas if your produce your units in a central area you will have to retreat your heavily damaged units to that spot. Of course buildings on your front line can be the enemies to use next turn if they capture it. You also have to decide what types of units to build, of which you have a reasonable amount to choose from - about 6 planes, 6 ships, 3 tanks, 9 or so types infantry, and various others - artillery, AT guns, support vehicles, AA, etc. A few units are only for certain countries, but most are just the same unit type with a different name, although each major country has advantages/weaknesses which can also factor in. Of course as well as paying to build these units, you also have to factor in the maintenance costs you then have to pay each week which can quickly start eating into your income.
There are some weaknesses though - the diplomacy didn't seem to work, or at least you get no real feedback so it is hard to work out why a deal was refused, or if the country in question just won't trade with you. Conquering a countries capital and capturing/killing its leader causes the country to surrender and the remaining territories become neutral (so you can have Vichy France effectively), but every time this happened for me they redeclared war a week or two later. You can land troops on any adjacent land, but to get back on the boat you need a port on the territory, this means in the pacific every time you land on a island you then have to built a port on it (taking two weeks) before you can get your army back. There is no troops limit in battles or on squares - each stack can only have up to 16 in it, but you can have as many stacks as you like in each place. This tends to end with large stacks building up and taking relatively undefended squares, rather than having broad fronts facing off against each other, and you can end up chasing behind an enemy single unit that keeps taking territories behind your front lines unless you fill up every place with at least 1/2 units, which gets expensive to maintain.
Overall I would say its okay for a quick and easy strategy game based on WWII, but it is probably better to step up to something like Making History or Hearts of Iron, as both of these titles do the same things but better, although admittedly they are more complex and take longer to get into (particularly HoI).