How to make 2D animation?

Question

2D

Advise how best to make 2D animation. It is desirable the program or an example.
There is a drawing - a man. You need to make a simple animation - walking, running.
I watched tutorial videos on skeletal animation. I present how it is done.
Photoshop (and a lot of things) I know.
In the search I found a topic where a person was advised the program creature.kestrelmoon.com
What good programs or online services for creating animation, hand-drawn video can you recommend?
This is the so-called skeletal animation. There are more weights, a grid, etc. (I didn’t understand much)
I downloaded it, looked, tried it. I didn't get good animation.
I have a problem with positioning. There is no grid in creature. There are no guides.
Positioning by coordinates, calculating them is a long time.
That is, in the same Photoshop, it is easy to set the position along the rulers and guides. There is no such thing in creature.
There are x and y. As a result, everything is done by eye. Or not by eye, but for a long time.
I have no idea how exactly to move the bones in a creature. There is no exact calculation of xy and the angle of desire (for a long time), and with the mouse - contour distortions occur. Leg extension for example. Which is obvious since the bone was stretched due to careless movement of the mouse. And to mathematically calculate the positions of all the bones - this is work for an hour. And then another move, with animation.
In the example, developers do everything with the mouse. And they don’t have such problems, since it doesn’t matter if the octopus’s tentacle is slightly deformed (it actually stretches) or the leg of a mythical creature bends a little. But with a person, these inaccuracies are immediately visible.
I'm starting to come to the conclusion that any 2D skeletal animation program will not produce a quality result. It's some sort of distortion. Maybe I'm wrong (I just got a bad sample program?).
For example, when the leg is bent, the program will be forced to deform the contour. The leg was straight - it became bent.
It is necessary to take this bend from somewhere, this distance. The program cannot draw the bend. And takes it from the contour attached to the bone, stretching the contour. This is for the straight legs of a flamingo, the tentacles of an octopus, the neck of a flamingo (in the same creature) does not matter. It doesn't matter how the flamingo's reed leg bends - it is straight. But the human leg - foot, lower leg, knee, thigh - volumes, position - is another matter. It's not a straight line that you can bend as you please or a flamingo's neck hose.
Basically, I need some advice. Perhaps creature.kestrelmoon.com is not the best program for this kind of animation.
I did not find convenient positioning tools there, which made me very upset (I spent time studying)
What can you advise? What program?
And perhaps, high-quality animation will still have to be drawn in Photoshop / Illustrator in order to control the bends and behavior of objects (legs / arms)? Also cut the picture into parts, position, draw.
(Ps Ai has excellent positioning tools.)
I don’t strive for Disney quality) I just don’t like animation from pieces (ala flash 2000x) or when the engine stretches the contours.

Answer 1

The best program, in my opinion, is Spine .
I advise you to master it. But she's paid.
Moreover, if you need a grid, then even more expensive.
It can't be hacked, so you'll have to buy it.
Of the free popular ones - Spriter . More precisely, it is paid, but there are torrents. Well, again, there is a free version. I also used it for a long time, but without the problems that you need. So I don't know if you're comfortable enough.