Messenger of Allah ﷺ used to pray (optional, non-obligatory prayer) while riding on his mount (Rahila) wherever it turned, and whenever he wanted to pray the compulsory prayer he dismounted and prayed facing the Qibla.  

كَانَ رَسُولُ اللَّهِ ﷺ يُصَلِّي عَلَى رَاحِلَتِهِ حَيْثُ تَوَجَّهَتْ فَإِذَا أَرَادَ الْفَرِيضَةَ نَزَلَ فَاسْتَقْبَلَ الْقِبْلَةَ  

The Prophet ﷺ used to pray (the Nawafil) on his Mount facing east and whenever he wanted to offer the compulsory prayer, he used to dismount and face the Qibla.  

أَنَّ النَّبِيَّ ﷺ كَانَ يُصَلِّي عَلَى رَاحِلَتِهِ نَحْوَ الْمَشْرِقِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ فَاسْتَقْبَلَ الْقِبْلَةَ  

[Machine] "When the Messenger of Allah ﷺ wanted to pray on his riding animal voluntarily, he would face the Qibla (direction of prayer), make the takbir (saying Allahu Akbar - Allah is the Greatest) for the prayer, then he would leave his riding animal and pray wherever it faced."  

كَانَ رَسُولُ اللهِ ﷺ إِذَا أَرَادَ أَنْ يُصَلِّيَ عَلَى رَاحِلَتِهِ تَطَوُّعًا اسْتَقْبَلَ الْقِبْلَةَ فَكَبَّرَ لِلصَّلَاةِ ثُمَّ خَلَّى عَنْ رَاحِلَتِهِ فَصَلَّى حَيْثُمَا تَوَجَّهَتْ بِهِ  

[Machine] The Messenger of Allah ﷺ used to pray voluntary prayers on his mount when he traveled to the destination. But when he wanted to pray the obligatory prayer, he would dismount and face the Qibla.  

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي عَلَى رَاحِلَتِهِ تَطَوُّعًا حَيْثُ تَوَجَّهَتْ بِهِ فِي السَّفَرِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ عَنْ رَاحِلَتِهِ وَاسْتَقْبَلَ الْقِبْلَةَ  

The Prophet ﷺ used to pray (the Nawafil) on his Mount facing east and whenever he wanted to offer the compulsory prayer, he used to dismount and face the Qibla. (Using translation from Bukhārī 1099)  

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي عَلَى رَاحِلَتِهِ نَحْوَ الْمَشْرِقِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ فَاسْتَقْبَلَ الْقِبْلَةَ  

The Prophet ﷺ used to pray (the Nawafil) on his Mount facing east and whenever he wanted to offer the compulsory prayer, he used to dismount and face the Qibla. (Using translation from Bukhārī 1099)  

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي عَلَى رَاحِلَتِهِ نَحْوَ الْمَشْرِقِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ فَاسْتَقْبَلَالْقِبْلَةَ  

The Prophet ﷺ used to pray (the Nawafil) on his Mount facing east and whenever he wanted to offer the compulsory prayer, he used to dismount and face the Qibla. (Using translation from Bukhārī 1099)  

«أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يُصَلِّي عَلَى رَاحِلَتِهِ نَحْوَ الْمَشْرِقِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ فَاسْتَقْبَلَ الْقِبْلَةَ»  

[Machine] "We were with the Messenger of Allah ﷺ in a battle, and he used to pray voluntary prayers on his mount facing the east. When he wanted to pray the obligatory prayers, he would dismount and face the Qibla."  

«كُنَّا مَعَ رَسُولِ اللَّهِ ﷺ فِي غَزْوَةٍ فَكَانَ يُصَلِّي تَطَوُّعًا عَلَى رَاحِلَتِهِ مُسْتَقْبِلَ الْمَشْرِقِ فَإِذَا أَرَادَ أَنْ يُصَلِّيَ الْمَكْتُوبَةَ نَزَلَ وَاسْتَقْبَلَ الْقِبْلَةَ»