Arabic Root:
From the root shin-kaf-ra (ش ك ر), which has the following classical Arabic connotations: to praise or commend for a benefit or benefits to acknowledge beneficence, to offer thanks, acknowledgement, to be thankful, grateful, to produce, supply, give forth bountifully.

There are two names here, Ash-Shakir (The Recogniser and Rewarder of good) and Ash-Shakur (The Appreciative). Al-Shakir is mentioned in the Qur'an twice, whereas Al-Shakur is mentioned four times. Below we've included an example of the usage of Al-Shakir, and you will see the name Shakur in other verses. One thing to note is that Shakur is more emphatic or exaggerated form.

۞إِنَّ ٱلصَّفَا وَٱلۡمَرۡوَةَ مِن شَعَآئِرِ ٱللَّهِۖ فَمَنۡ حَجَّ ٱلۡبَيۡتَ أَوِ ٱعۡتَمَرَ فَلَا جُنَاحَ عَلَيۡهِ أَن يَطَّوَّفَ بِهِمَاۚ وَمَن تَطَوَّعَ خَيۡرٗا فَإِنَّ ٱللَّهَ شَاكِرٌ عَلِيمٌ

Innas Safaa wal-Marwata min sha’aaa’iril laahi faman hajjal Baita awi’tamara falaa junaaha ‘alaihi ai yattawwafa bihimaa; wa man tatawwa’a khairan fa innal laaha Shaakirun Aleem

English Translation:
"Indeed, as-Safa and al-Marwah are among the symbols of Allah. So whoever makes Hajj to the House or performs ‘umrah – there is no blame upon him for walking between them. And whoever volunteers good – then indeed, Allah is appreciative and Knowing."— (Qur'an 2:158)

Ash-Shakur is a display of the expansiveness of Allah's love. He is the one who has given us the gift of life. Everything we see, love, and touch are because Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ has allowed it to be that way. Yet He tells us, He appreciates and accepts all deeds, no matter how small. He is all-watchful and all-grateful to us.

مَّا يَفْعَلُ ٱللَّهُ بِعَذَابِكُمْ إِن شَكَرْتُمْ وَءَامَنتُمْ ۚ وَكَانَ ٱللَّهُ شَاكِرًا عَلِيمًۭا

Maa yaf’alul laahu bi ‘azaabikum in shakartum wa aamantum; wa kaanal laahu Shaakiran Aleema (End Juz 5)

English Translation:
"What can Allah gain by your punishment, if ye are grateful and ye believe? Nay, it is Allah that recogniseth (all good), and knoweth all things."— (Qur'an 4:147 )

Multiplying good deeds:
Moreover, He is the one who multiples the rewards of His servant's many folds. It is also only Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ who has the power to multiple without any measure or restriction. As an illustrative example, here's what the Messenger of Allah ﷺ said on good deeds committed while fasting: "Every good deed of the son of Adam will be multiplied manifold. A good deed will be multiplied ten times up to as many as seven hundred times, or as much as Allah wills." ^[1] Also, Ibn Umar narrated that one day: The Messenger of Allah ﷺ said to his Companions: “Say ‘Glory is to Allah and with His Praise (Subhan Allah, wa bihamdih) a hundred times. Whoever says [it] one time, it is written for him ten, and whoever says it ten (times), it is written for him a hundred, and whoever says it a hundred (times), it is written for him a thousand, and whoever increases, Allah will increase for him, and whoever seeks Allah’s forgiveness, [Allah] will forgive him.” ^[2]

Pairing Al-Ghafur and Al-Shakur:

وَقَالُواْ ٱلۡحَمۡدُ لِلَّهِ ٱلَّذِيٓ أَذۡهَبَ عَنَّا ٱلۡحَزَنَۖ إِنَّ رَبَّنَا لَغَفُورٞ شَكُورٌ

Wa qaalul hamdu lillaahil lazeee azhaba ‘annal hazan; inna Rabbanaa la Ghafoorun Shakoor

English Translation:
"And they will say, “Praise to Allah, who has removed from us [all] sorrow. Indeed, our Lord is Forgiving and Appreciative –"— (Qur'an 35:34)

This pairing of names here conveys Allah's nature of showing mercy and seeing the good in us. Put another way, He frequently forgives, cleansing us of our many sins. He is also accepting of all good that we do, no matter how inconsequential it may appear.

The promise of Jannah:
The promise of an eternal paradise for a short-lived time on earth doing good deeds is an example of an immense reward for relatively little effort. In the Qur'an, it says to the people in paradise, "[They will be told], 'Eat and drink in satisfaction for what you put forth in the days past.'" (Qur'an 69:24) Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ recognizes and rewards the action of His servants. This is why it's important to do good, even when no one sees it. To do good for its own sake because Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ will reward us for it. Any acknowledgment from the outside world is a bonus. Being recognized through an award is nice to have. The real reward we should seek is from Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ who always gives within measure or more than what's due.

Reflection:
A believer benefits from knowing that Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ is al-Shakur. If Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ can be grateful to His servants when He has no need to be, and He continually forgives and rewards; then perhaps we can learn to be the same amongst ourselves. In a hadith, Prophet Muhammad ﷺ conveys a similar message, "He who does not thank the people is not thankful to Allah." ^[3]

This is also a reminder to thank Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ, praise Him for His gratitude. Even this will render some benefit to you, as Allah سُبْحَٰنَهُۥ وَتَعَٰلَىٰ says in the Qur'an, "If you are grateful, I will surely increase you [in favor]" (Qur'an 14:17) and also, "If you disbelieve – indeed, Allah is Free from need of you. And He does not approve for His servants disbelief. And if you are grateful, He approves it for you; and no bearer of burdens will bear the burden of another. Then to your Lord is your return, and He will inform you about what you used to do. Indeed, He is Knowing of that within the breasts [hearts]." (Qur'an 39:7). Our praise and obedience will work in a loop that only further propels us to the entrance of Jannah. We can never do enough to repay the blessings He has bestowed on us. We should try to keep this front of mind as we can feel immense happiness and love to know we have such a loving and appreciative creator.

ذَٰلِكَ ٱلَّذِي يُبَشِّرُ ٱللَّهُ عِبَادَهُ ٱلَّذِينَ ءَامَنُواْ وَعَمِلُواْ ٱلصَّـٰلِحَٰتِۗ قُل لَّآ أَسۡـَٔلُكُمۡ عَلَيۡهِ أَجۡرًا إِلَّا ٱلۡمَوَدَّةَ فِي ٱلۡقُرۡبَىٰۗ وَمَن يَقۡتَرِفۡ حَسَنَةٗ نَّزِدۡ لَهُۥ فِيهَا حُسۡنًاۚ إِنَّ ٱللَّهَ غَفُورٞ شَكُورٌ

Zaalikal lazee yubash shirul laahu ‘ibaadahul lazeena aamanoo wa ‘amilus saalihaat; qul laaa as’alukum ‘alaihi ajran illal mawaddata fil qurbaa; wa mai yaqtarif hasanatan nazid lahoo feehaa husnaa; innal laaha Ghafoorun Shakoor

English Translation:
"It is that of which Allah gives good tidings to His servants who believe and do righteous deeds. Say, [O Muhammad], “I do not ask you for this message any payment [but] only good will through kinship.” And whoever commits a good deed – We will increase for him good therein. Indeed, Allah is Forgiving and Appreciative."— (Qur'an 42:23)

The Prophet (ﷺ) said, "I saw a man going about in Jannah (and enjoying himself) as a reward for cutting from the middle of the road, a tree which was causing inconvenience to the Muslims." According to the narration in Al-Bukhari and Muslim: Messenger of Allah (ﷺ) said, "While a man was walking, he saw a thorny branch on the road, so he removed it and Allah appreciated his action and forgave him." ^[4]

References:
01) Sahih (Darussalam) Sunan Ibn Majah 1638
02) Hasan (Darussalam) Jami at-Tirmidhi 3470
03) Sahih (Al-Albani) Sunan Abi Dawud 4811<
04) Riyad as-Salihin 127