Samsung is the largest smartphone manufacturer worldwide since many years. However, as Chinese companies such as Xiaomi, OPPO and Vivo have expanded to other territories, the Korean giant has seen its market share shrink, keeping Apple always in second position.
As stated by Trendforce, Apple could overtake Samsung in the last quarter of 2021, since it would reach a market share of 23,1%, going from 15,9% in the third quarter of 2021. Samsung, for its part, would lower its market share from 21,2% to 19,4%.

In the report published by this medium, we can read:
The smartphone market is showing an improvement in demand during the second half of this year due to the peak season of e-commerce promotional activities and the decline in COVID-19 outbreaks in regions such as Southeast Asia, according to the latest TrendForce Research.
However, there has been a significant shortage of components, including 4G SoCs, low-end 5G SoCs, display panel driver ICs, etc. Persistent component gaps are preventing smartphone brands from increasing device production for the second half of the year […]
Moving forward, an important point of observation in the smartphone market is whether the pandemic will further weaken demand.
Although it is true that Apple increases its market share during the last quarter of the year due to Christmas sales and that it has presented new models, this year, things are complicated due to lack of supplies that are already affecting the availability of the iPhone 13.
Honestly, an 8% jump in market share in just one quarter is impressive considering the lack of supplies and manufacturing problems Apple and other manufacturers are experiencing. We will have to wait until February to see if this prediction is confirmed.