// instantiation
APAsyncDictionary *dictionary = [[APAsyncDictionary alloc] init];
...
// get object for key
__block id someObject;
[dictionary objectForKey:@"key" callback:^(id <NSCopying> key, id object)
{
    someObject = object;
    // do something with object
}];
...
// get object for key synchronously
someObject = [dictionary objectForKeySynchronously:@"key"];
...
// set object
[dictionary setObject:object forKey:@"key"];
...
// set objects and keys from dictionary
[dictionary setObjectsAndKeysFromDictionary:@{@"key1" : object1, @"key2" : object2}];
...
// remove object for key
[dictionary removeObjectForKey:@"key"];
...
// remove objects for keys from array
[dictionary removeObjectsForKeys:@[@"key1", @"key2"]];
...
// remove all objects
[dictionary removeAllObjects];
...
// get objects count
[dictionary objectsCountCallback:^(NSUInteger count)
{
    // do something with count    
}];
...
// get objects count synchronously
NSUInteger count = [dictionary objectsCountSynchronously];
...
// all keys
[dictionary allKeysCallback:^(NSArray *keys)
{
    // do something with keys
}];
...
// all objects
[dictionary allObjectsCallback:^(NSArray *objects)
{
    // do something with objects
}];