The Pixel 4a is a smartphone announced by Google 
on August 3, 2020 that runs Android. It is the successor to the Google Pixel 3a and the second in a series of mid priced ($300-$500) smartphones from Google.
I ordered the Pixel 4a on August 3, 2020 to replace the Pixel 2 and it is expected to ship on August 20, 2020.
Given that the Pixel 4a is the same size as the phone it replaces, I am hopeful that it has longer battery life. It has a larger battery and I expect it combined with the "lower powered" 730G processor will make a significant difference.
The Pixel 4a has nearly the same physical dimensions as the Pixel 2 but has a larger (5.81" vs. 5.0") screen. The Pixel 4a has a Qualcomm Snapdragon 730G processor, 6 GB of RAM, and 128 GB of storage. Unlike the Pixel 2 that has a aluminum and glass case, the Pixel 4a has a polycarbonate case. Android Authority
The physical dimensions of the Pixel 4a is that it is 5.7 inches tall, 2.7 inches wide, and 0.3 inches (8.2 mm) thick. I think these are ideal dimensions and I am loath to have a larger phone.
It really is a struggle to find meaningful flaws in this phone—and I'm serious about that. For the money, it is genuinely hard to imagine a way Google could make a better smartphone. In that sense, it feels like the Nexus that never was: cheap, uncompromising, and with a camera you'll actually want to use. AndroidPolice
I received the Pixel 4a that I ordered on August 21, 2020 and immediately had problems . Upon moving the SIM card from my Pixel 2 to the 4a, during the setup process, I noticed that the 4a did not connect to the AT&T network. Troubleshooting began, contact with Google Support was made, and in the end it looks like the mobile radio is defective as the power toggle for it does not stay on. It will be exchanged for what I hope will be a working phone. While I understand that 100% of the phones will not have defects, something that does not work from the moment you take it out of the box is a horrible user experience.
Received replacement on August 28, 2020 and it connected to AT&T as expected. I am now using the Pixel 4a as my every day carry. Right now I can report that battery life is better than the Pixel 2 with AccuChek Battery Pro showing 2% discharge rate while the screen is off, compared to 3.5% of the Pixel 2.
I've specifically decided to not install the Android 11 beta on the Pixel 4a as I think in a matter of weeks the official release will be pushed. Sticking with Android 10 for now enables me to partake in Google's intended 4a experience.
On September 8, 2020 Google released the production version of Android 11 that I installed on my Pixel 2 and Pixel 4a.
On August 11, 2021 I installed the final beta of Android 12 on the Pixel 4a. On October 4, 2021 Google released the production version of Android 12, which installed on the Pixel 4a shortly there after.
On February 2, 2022 I read reports that Google has removed the Pixel 4a from their online store, which is a little under two years after its release. Google will continue providing updates to it until August, 2023, three years after its release.