The 11th Skandha is famous for its two subjects viz. 1.Bhagavata Dharma as taught by the nine sages 2. Uddhava Gita. These two topics elaborately deal with Bhakti, Jnana and karma yogas stressing at the same time the necessity for devotion. The main topic of discussion is Moksha, the attainment of illumination and liberation from the cycle of Samsara. Along with the 10th canto, this Skandha is the crowning cope-stone of the edifice of the Bhagavatam.

A separate article of mine appears in this website exclusively on the Uddhava Gita . This Skandha ends with the final destruction of the Yadava Clan to which Krishna himself belongs by internecine fighting as also the end of the Krishna Avatar when Krishna exits after being shot at by a hunter.

The 12th Skandha is a sort of concluding remarks where it says that though the Kaliyuga has been pictured as an evil age, it affords favorable circumstances for the practice of devotion through chanting and singing of the divine name. A synopsis of the whole Bhagavatam and the ceremonial way of studying it were included in this canto.

The significance of the Skandha lies in the fact that it deals with the Supreme Being as the substratum into which every thing dissolves and finds its ultimate refuge. 

Here Bhagavatam is eulogised as the quintessence of all Vedanta’s based on the truth of non-duality and characterized by the unity of Atman and Brahman. Its ultimate purpose is liberation and contains in it both the theory and practice to achieve this end. (12.13.12) Being the quintessence of Vedanta, one who has enjoyed the nectar of its rasa will never have any desire for anything else.(12.13.15) Vedanta is like a tree, the Bhagavatam is like a ripe fruit.

Just as Ganga is the most superior among rivers, Vishnu among the divinities, Sambhu among the devotees, so is the Bhagavatam among the Puranas. (12.13.16) The Bhagavatam is unrivalled among the Puranas as Kasi is among the holy places. (12.13.17)

Apart from being the essence of Vedanta, the Bhagavatam contains in many places the very words and similes used in the Upanishads and the Bhagavad Gita. E.g. Bhagavatam (4.29.18-19 - Kathopanishad 1.3.3), (7.15.42 - Mundakopanishad), (8.1.10 - Isha Upanishd,Verse 1), (3.28.11 - Amritanadopanishad, Verse 8 & Patanjali Yoga Sutras), (10.81.4 - Bhgavad Gita 9.26), (11.11.32 - Bhagavad Gita 18.66)

The last verse of the Bhagavatam offers salutations to the Lord saying “by chanting Hari’s name man is freed from all sins, by surrendering to whom by prostration, he is saved from all misery.” (12.13.23)

Bhagavatam and Advaita
Many would be surprised to see the above caption.  However, it is not a matter of surprise but an actual fact despite several  contrary viewpoints. The Bhagavatam frequently discusses the merging of the  individual soul with the Absolute Brahman, or "the return of Jiva into His  own true nature", a distinctly advaitic or non-dualistic philosophy. In  the same passages, the Bhagavatam still recommends Bhagavan as the object of  concentration for reaching that goal. Scholars describe this philosophy as  "Advaitic Theism", which combines the seemingly contradictory beliefs  of a personal God that can be worshiped with a God that is immanent in creation  and in one's own self. Daniel P. Sheridan describes Advaitic Theism as a  "both/and" solution for the question of whether God is transcendent  or immanent in relation to creation, and credits the Bhagavatam with a  "truly creative religious moment" for introducing this philosophy.

Bhagavatam and Karma Yoga
Krishna told Uddhava in the 11th  Skandha, 20th chapter: “In order to lead men to the highest good,  three methods of self-discipline have been taught by me. They are -
1. Jnana Yoga, the path of knowledge or investigation - meant for those who have lost the taste for worldly action, considering it to be a source of misery
2. Karma Yoga, the path of action - meant for those who thirst for fulfillment of desires through action and 3. Bhakti Yoga, the path of devotion meant for those who are neither disgusted with sense pleasures nor inordinately attached to  them. And who love to hear the stories about the Lord and chant his name.

Those who follow any one of these  paths will attain the state of Brahman, the absolute Reality, my state.”

The Lord made it clear that so  long as one clings to worldly pleasure and has not developed devotion, he  should perform his duties according to the instructions of the scriptures. He  who worships the Lord through Yajnas with desire for its fruits goes neither to  heaven nor to the other regions, but continues to take human bodies from birth  to birth till he attains Jnana and Bhakti to him.

Bhagavatam and Yoga Sutras
In reply to an earlier question by King Parakshit,  Śuka tells him in the beginning of the 2nd Skandha a classical  approach to yoga like making an asana (place to sit) in a solitary place and  meditating on Om, without regard for the distractions caused by the lower  qualities of raja and tamo Guna. Śuka also describes different meditations on  the gross and subtle aspects of Bhagavan, or God, in a way that is similar to  the Yoga Sutras of Patanjali.

Several passages describe the merging of the  individual soul with the Absolute Brahman. The Bhagavatam, in explaining the  method of reaching that goal, recommends the object of concentration as Bhagavan,  with an emphasis on yoga as a form of Bhakti.

Siddhis, or spiritual powers developed through yoga  practice, are described in many passages in ways that echo the Yoga Sutras of  Patanjali. The tenth chapter of the 11th    Skandha teaches that the yogi who has  controlled his senses and concentrated his mind on Bhagavan develops these  siddhis. Patanjali describes siddhis as obstacles to reaching the ultimate goal  of yoga (union) while the Bhagavatam describes them as blessings that are  present in Bhagavan in infinite form, and given to the yogi in varying degrees  depending on the yogi's devotion.