"Old" Smartphone Android.... Free Wifi calls

So "Service Google Play" is out of date...
Even Chrome requires it...but phone says it is not compatible...

Consider using Text Messaging. That might work for you.

Otherwise, consider upgrading the phone to something newer and supported.

Thanks but no... Don't want to buy a new phone for my daughter. And text is not enough, need calls over wifi...Worst case, ok to buy credits

The age of the device should not be a problem. You may be short of memory though. Here is a site that offers more specific help.

http://thedroidguy.com/2016/02/samsung-galaxy-s5-software-update-interrupted-issue-other-related-problems-1055343

Search for free texts from internet .... plenty of options there.

You can also buy texts from http://www.easytext.eu/
or consult this list
http://mashable.com/2008/04/19/send-text-messages/#.cdJtzAHYkqt
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Most people seem to be fooled by Pay-As-You-Go monthly payments/plans
They are typically advertised as 20 €/$ per month and people think you have to pay each month ... You don't!
A €20 top up can last many years (You just pay Out-Of-Package call/text charges).

I have a working O2 number (now Three) that I have not topped for over 12 years.
(I have it on a GSM Gateway Device / PABX for convenience)
I just dial 171 every 4 months to keep it alive.
I use it for incoming calls only from specific people/organisations.
I also get 500 free webtexts a month.

Check your t&c .... most times you only have make ONE call every 6 months.
With Vodafone you have to topup by at least €5 every 7 months.

So top up the phone when the credit runs low -- NOT every month.
With an active SIM, your daughter can text you (or call you and hang up) when she is away from a hot spot and you call her back.

Don't forget 112 emergency calls can always be made (even without a SIM card).
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Try the keep calling app
https://www.keepcalling.com
I highly recommend them -- There is no minimum usage and your credit NEVER expires.

I was / am thinking of doing the same thing - because I hate Android but a friend gave me a Samsung S4 and I can connect it to my Windows phone.  

I have a Google Voice Number, so I thought that would help some.  But I came across a few articles that I have not had the chance to completely read On CSH1545 with 4.3 Android Version):

• How to Use Google Hangouts For Free Wi-Fi Calls and Texts
• Make calls with Hangouts on Android
• Send & receive text messages
• Receiving a phone call in Gmail
• making a google voice call with 100% wifi, and no cell coverage or 4G network available?

(old but I think that Hangouts is probably the answer)
You might want to ask them over there in their forum.   Or you can call Google Play Store (855_836-3987 - they might be able to tell you what app(s) to download.

Just go to the link below to download the .apk file for Skype version 7.03.0.558.

http://www.apkmirror.com/uploads/?q=skype

and Enable ‘unknown sources’ from settings>security and you will be able to install the Skype app via the apk file.

OR

Have you done a factory reset of your S5 mini?

Skype shall run on Android 4.4.4 and there is no need to update Google Service just for installing Skype.

All
Just to be clear:

- I did a hard rest of the S4 mini and erased evenrything
- I configured the phone with my daughter's gmail account
- Installed Skype (regular and Wifi) and Hangouts

The issues are

1- I get notifications that the "Google Play" services are outdated
2- when I try to update, it tells me the phone (s4 mini, Android 4.4.4) is not compatible
3- This update looks required for using Skype or Hangout or even the latest version of GMail that has been automatically installed

In addition

- I am looking for a good and reliable app that enables text and VoIP using Wifi only and no sim card in the phone

If definitely want no SIM, try my KeepCalling suggestion
https://www.keepcalling.com/apps_voice

Eirman: this last solution looks interesting as I am based in South Korea...
Will update soon

If you are in Korea, why not use the LINE app?

Apart from LINE app, you can just try wechat app.

Line requires a phone number for activation, and I have not. I think Eirman has the best answer for my need.