is there a minimum texture size a certain hardware needs to support to be compliant with the OpenGL-ES 2.0 specification ?
Something like the GL_MAX_TEXTURE_SIZE value has to be at least 1024 or 2048 or something like that ?
The reason I would like to know this is because I work on something that uses shaders and as such has to be OpenGL-ES 2.0. Therefore I would like to make the textures as big as possible without having to consider each and every hardware texture limitation (like the old phones with only 512x512).
If there was a minimum number (or a certain value that most devices support) that would help me alot.
Yes, any GLES2 implementation must support at least 64 pixel texture in width and height. You can query actual actual max texture size with glGetIntegerv function using GL_MAX_TEXTURE_SIZE enum.
See official spec page 141, table 6.20.