On Facebook and mobile, there are hundreds of games that let you play for free and then charge tiny amounts for in-game bits and bobs. To help you navigate the world of freemium, we'll show you how far you can make, say, a fiver or a tenner stretch in the biggest free-to-play titles. Outernauts - aka Pokemon in spaaaaace! - is the first social gaming release from Ratchet and Clank developer Insomniac. And what a first it is! It deftly mixes Pokemon-style battling with a mission-based social gaming structure.

There are many areas in which you can spend your real-life cash in this free-to-play title. Some are practical (to boost stats and the like), while others are vanity items (for dressing your character up in galaxy-saving attire).

For £5, you can grab yourself around 78 star gems (Outernaut's real-world currency) - note that you can only buy gems in denominations of $5. Since we're British and proud at Pocket Gamer, mind, we're going to rebel and stick with our own currency, a-thank-you-very-much.

So, what can you get for your hard-earned fiver? Here are several ideas to consider.

Extra party slot

You start Outernauts with just three party slots to hold creatures in, and if you want to bring more than that (up to six total) into battle, you'll need to buy more slots using star gems.

Each slot costs 50 gems. So, for your £5, you'll be able to purchase one extra slot. Buying an extra slot makes a huge difference, as you'll suddenly have an entire extra creature to battle with.

It especially makes a difference later on in the game when you have whole teams of six to battle - this can be rather tricky with only three creatures at your disposal.

Creature move slots

Each of your creatures can initially remember up to four different battle moves, à la Pokemon. However, you can fork out some star gems to unlock up to four more slots.

The fifth slot always costs 25 star gems, although each subsequent slot for a single creature costs more (50 gems, then 75, then the final, eighth slot of 100).

You don't particularly need more than five slots, for five gives you a great range of abilities to choose from for each of those tricky situations. Since the fifth costs 25, you could potentially buy an extra slot for three of your creatures with £5.

Expanding your homeworld

Your homeworld is titchy - so titchy, in fact, that you'll run out of space to put buildings down fairly quickly.

Annoyingly, to expand your homeworld, you need Pyrite, and you can only earn this by asking your Facebook friends to get it for you. If you don't have any friends who play the game, this can prove troublesome.

Fortunately, you can also use star gems to grab Pyrite. Each Pyrite chunk costs five star gems, and you'll need two chunks to upgrade, which isn't too bad at all. You'll have plenty of money left over for other things.

Spacesuit attire

Customising the look of your hero isn't just about improving his appearance - each piece of clothing has its own stat advantages, too, such as giving you immunity to status effects.

Unfortunately, every piece of clothing costs real-money gems. The majority cost 20 star gems, so to grab a helmet, suit, gloves, and shoes, you're looking at forking out 80 star gems - just above our £5 budget.

Note, however, that you can unlock a good number of the suits through just playing the game, so we'd suggest you grab a helmet, gloves, and shoes and leave the suit.

Want more? Check out our growing collection of Outernauts articles!