I remember reading about Fling as a telekinetic manipulation spell that required physical touch. How does this make any sense? Im pretty sure it is the only Tele. Manip. spell that requires physical touch. My question is What is the advantage of this spell if I remember correctly you have to physially touch an object in order to fling it. How is this any more advantagious than actually throwing the object?

Less drain.

Telekinetic Manipulation spells by nature infer that you move things without actually having to touch them. Take Magic fingers for instance. My question is how would fling be any more advantagious than actually throwing the object? As far as drain goes why not just use a sustaining focus?

A mage with Strength-2 and no Thrown Weapons skill would find Fling-6 advantageous.
A mage with both hands tied behind his back would find it advantageous.

Magic Fingers doesn't let you use Sorcery as your Ranged Combat skill. It also applies a +2 TN modifier to any skill used remotely. Sustaining it may reduce drain, but it doesn't affect these limitations.

Levitation would be similarly limited, but wouldn't impose the TN modifier. In addition, the damage you could do with, say, a throwing knife may be limited to (movement rate / 10) Stun depending on your GM's interpretation of the spell description. Lastly, a sustaining focus for a Levitation spell against a grenade would only work as long as the grenade existed. Once it blew up, you'd have to recast the spell against a new valid subject.

You could create a new fling without the touch requirement. The drain would be higher, but other than that, it should work the same.

That thought occured to me how about 2m drain like magic fingers?

Grenades can hang off belts and bandaleros. Shuriken can be disguised as jewelry (rings, earrings, brooches, lapel pins, tiaras, torqs, etc.). If you're lying on the ground, touch your head (or leg, or butt, etc.) to the nearest rock and bingo!, you're armed.

Unless you have some sort of geasa, there's nothing forcing you to use your hands as the sole focal points for magic.

Fling is built using the spell design rules in Magic in the Shadows (MITS). A modified version of Fling (one that uses LOS instead of Touch) can be built using these rules as well. However, the drain goes up; +1(S) instead of +1(M).

Most of that makes sense but the drain isnt really an issue just use a sustaining focus.

Fling is an Instant spell. It cannot be placed in a sustaining focus.

Stupid me. In about a month when I have access to the books again ill read up on that.

Aptitude would help, but the Shadowrun Companion (SC) specifically advises against allowing players to take the Aptitude edge for combat and magic skills. It can be too unbalancing. Your GM'll have the final say on this.

I've allowed weird aptitudes before. One of my players had a character with Aptitude: Dodging, which I allowed with the proviso that he wear only form-fitting or second-skin armor. Another wanted Aptitude: Blowjobs which I gave him a discount for.

It's cool to be good at something weird, like Aptitude: Magic Fingers Swordfighting

I'd certainly allow something like an aptitude for spellcasting with a specific spell category - so long as the character wasn't already a relevant shamist or elemental mage because that's just cheesy.